Various library related notes

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For more articles related to library systems, see the Library related category. Some of the main articles:

Library glossary

This hasn't been updated for a while, so could be outdated (particularly if it's about something that evolves constantly, such as software).

General library terms, cataloguing terms, library automation terms

  • AACR: Anglo-American Cataloguing Rules
    • a list of rules often followed when creating records in a cataloguing system
    • apparently based on ISBD (verify)
    • AACR2 / 'AACR II': ...Second Edition [1] [2]
    • AACR3 is the informal name for the next, currently future version (expected in 2009), which is more formally titled Resource Description and Access (RDA) [3].
  • Added entries - See Main entry
  • Authority file / records (occasionally abbreviated to 'authorities') (see also record types): An authority file, containing authority records, is an index separate from a bibliographic item catalogue, and contains indexing decisions made by cataloguers at a library, to use consistent forms (optionally taking them from elsewhere for further consistency) for thing that could appear in various spellings/forms (authors, subjects, etc.). Meant primarily to be used when when cataloguers create or revise item records. Authority files are regularly used for things like author names, place names, corporate names, subject headings, uniform/series titles, and such. (verify) See e.g. [4] [5]
  • Bath profile is a set of conventions that makes Z39.50 more interoperable when adhered to [6] [7]
  • Bibliographic record - see Record types
  • Call number: A code assigned to a book to show its location in a library's shelving system, usually clearly containing the classification used in the librar, because they are usually closely tied to the book/room classification system.
  • Cataloguing rules/manuals: the set of rules followed when entering an item into a catalogue. See AACR2, and also various others like LCRI, ISBD, USBD, APPM, GIHC, and various other things that have something to say about something or other.
  • Cataloging record: The information historically shown on a catalogue card. Often a bibliographic record (see record types below), but may contain most any other information related to a resource.
  • Classification record - see Record types
  • Community record - see Record types
  • Crosswalk: a mapping between metadata record types standards
  • Database, Target, Source and probably some other terms are use for (remote and searchable) sources of information. Also compare with 'repository'. Can be merely bibliographical (offering citation data), be part of a library that offers the books, electronic system that offers full-text articles, or some mix of this.
  • Gray literature: Literature that cannot easily enter mainstream distribution/subscription, and historically was hard to locate, but may sometimes still be popularly cited because of its specialized and often quite recent nature. Grey literature includes white papers, preprints, technical reports, and working papers, and may come form research groups, committees, government agencies, and such. Also refers to items that were never published, be it officially or at all. [8]
  • Federated search: the simultaneous search in multiple, often remote databases. Note that some use this term interchangably with metasearch, while others point out differences such as that metasearch focuses more on merging and/or often uses systems accessible in other ways, while federated search often searches in restricted/licenses databases.
  • FRBR ('Functional Requirements for Bibliographic Records'): refers to a model of semantic interrelations between works, realizations, items, responsible entities, and others. People may use the term loosely, as an adjective to describe things such as the LibraryThing ISBN-work mapping, but also for some other types of semantic cross-relations.
  • Hidden web: A term used to refer primarily to online content that not searchable via general web search, usually because it is licensed.
  • Holding record - see Record types
  • ISBD: International Standard Bibliographic Description [9] [10] (see cataloguing rules, and also AACR)
  • Main entry, added entries: Back in the time of paper catalog, when cards represented entries, it was be sensible to have one real entry, and have entries for alternative titles, alternative authors and such refer to that one main entry card, amongst other reasons to avoid having to change information in more than one place. This model is still used in various electronic catalogues.
  • MARC and MARCXML: Formats that metadata may be transferred in. Note that the name MARC groups many specific MARC implementations.
  • MARC8: A character encoding used in some MARC formats. [11]
  • Metasearch - see (notes on) Federated search
  • Microform, Microfilm, Microfiche: Microform is the general term referring to content recorded on film at reduced size. Two common forms are microfiche sheets (often 4" by 6" or 3" by 5") and the reel-based microfilm. (verify)
  • Monographs: In the library context, any non-serial publication (usually a book) or a very finite serial one (e.g. an encyclopedia). (Outside of library context, it often refers to an academic publication on a single subject or or person, often in a complete or authoritative sense) (compare with serials)
  • MXG (Metasearch XML Gateway): A gateway to ease metasearch, (strongly) preferring SRU
  • OAI: 'Open Archives Initiative' [12]
    • OAI-PMH: A Protocol for Metadata Harvesting, used to transfer repository content. [13]
  • OPAC: Online Public Access Catalog, often just 'online catalog' (Regularly, but not necessarily used to refer to public library catalogs meant for end users). Note there is also a record format named OPAC(verify); see below.
  • OpenSearch: A search-and-present protocol [14]
  • OpenURL [15]: a metadata standard for citation data coded (usually in a URL), to be parsed by an OpenURL resolver, which sends users to appropriate services for a particular library's users. It brings resolving closer to the user in the currently license-segregated world of full-text.
  • Record types: the types of data a metadata record can store. MARC mentions the following as concepts (and can store them):
    • Bibliographic record: physical and intellectual characteristics of a resource
    • Classification record: (could be seen as a semantic extension of a bibliographic record)
    • Holding record: copy-specific information on a library resource such as call number, shelf location, and/or volumes held
    • Authority record: A record that shows the established or preferred form of names, titles, regions, terms, subjects, etc.
    • Community record: can be used to describes individuals (details such as expertise), organizations, (public) services, public places, associations, agencies, and also event information like a lecture, concert (series), celebration, regular meeting, or such.
  • Repository: a store of information, usually without a search index or search interface worth mentioning
  • Serials: refers to serial publications, which groups things such as journals, magazines, and newspapers. (compare with monographs)
  • SRU: A search-and-present protocol [16]
  • SRW: An adaptation of SRU that works over SOAP
  • Subject headings: Also related to the physical catalogue days, in that a controlled set of subject headings would mean related items could be placed in the same spot in the catalog, without having to deal with synonyms and such.
  • Z39.50: A search-and-present protocol [17]

More identifiers and classifiers

(separate from the above mostly because some of these are quite rare/local)

Note that this mixes general, wider use, and union system stuff, as well as and narrower, relatively locally local used identifiers.

Name, abbreviation Identifies/enumerates what? Local or generic? Further notes Interesting links
ARK (Archival Resource Key) 'Objects' Persistent identifiers, URN-like in setup [18] [19]

arXiv identifier Articles(verify) mostly system-local [20] (narrower use)
Astrophysics Bibcode Articles mostly system-local Used in the Astrophysics Data System and some others. [21]
BICI, Book Item and Contribution Identifier Monographs (In development) apparently an ISBN-compatible, SICI-style system for books [22]
Bliss Classification classification/subjects  ? [23]
Canadiana number (narrower use) Records/items system-local Used by the National Library of Canada
CODEN Serials Six-character alphanumeric code. Not used that much. [24]
CNRI Handle 'Objects' DOI is one system based on Handle, there are others. [25]
DAI, Digital Author Identification identities Also known as Digitale Auteur Identifier, and as NTA number (Nationaal Thesaurus voor Auteurs){{verify{{
Dewey classification/subjects fairly wide-spread Known as Dewey Decimal System, Dewey Decimal Classification (DDC), and more. A three-number, tiered classification system [26]
Document Object Identifier, DOI 'Objects', often articles theoretically general-purpose Persistent object identifier system, usable (resolvable) on the internet.

In the context of libraries, DOIs usually refer specifically to articles.

EAN products/objects widespread In the library context this reference to EANs usually refers to bookland (978) EANs, which encapsulates ISBNs [27]
ERIC number (narrower use) Records/items Narrow; to/in system
ISAN 'audiovisual works' narrow? 'International Standard Audiovisual Number' [28]

ISBN Monographs Note that thirteen-digit ISBNs (required of publishers since January 2007) are actually part of EAN-13 barcodes[29], which absorbed ISBNs into bookland (978 prefix). (Currently, there is only one prefix, so there is currently a 1:1 mapping between ISBN10 and ISBN13) [30]
ISM (ISM Library Information Services, formerly Utlas)
ISMN (International Standard Music Number) Printed music narrow? [31]
ISNI, International Standard Name Identifier Identities Under development [32]
ISRC (International Standard Recording Code) Sound recordings,
music video recordings

ISSN (International Standard Serial Number) serials Note: an ISSN for which it is known that it refers to and electronic form (particularly amongst alternatives) is sometimes called an eISSN (sometimes ESSN) [34]

ISWC (International Standard Musical Work Code) 'musical works' narrow Works, not recordings. Mostly used by copyright collectives? [35]

JACS (Joint Academic Classification of Subjects) academic [36] [37]

LCC: Library of Congress Classification classification/subjects Various other libraries use it (see also below) [38]
LCCN: Library of Congress Control Number bibliographic (most), also (name?) authority records, classification(?) in LoC, but also beyond (see also below) interesting as wider identifier, mostly simply because LCCNs are a large set [39]
LCSH (Library of Congress Subject Headings) subjects (see also below) [40]
MeSH: Medical Subject Headings classification/subjects A detailed chemical/medical subject system, from NLM [41]
NAL number (National Agricultural Library) Mostly local
NBC BCL', BasisCLassificatie classification Dutch university libraries, mostly used in [42]
NBN (National Bibliography Number) Records/items a few systems (mostly in Scandinavia?) (narrower use) an URN-like item identifier [43] [44]
NLM: 'National Library of Medicine' mostly local Can also refer to the NLM classification system, which is an extension to LCC. [45]
OAI identifiers mostly local are URNs that contain the maintaining/source organization for a record (so could be used in a globally unique way)
OCLC number' (OCLC control number) records/items In worldcat, and beyond An item identification code used in OCLC WorldCat to refer to books, articles, journals, CDs, video, computer files, and more. A pretty large set (union of many libraries), so useful as a switchboard sort of identifer (like LCCN) [46]
PMID, Pubmed ID Articles System-local A record identifer used in Pubmed and some derived sources [47]. Works as a PURL-type service through [48]
PPN (Pica Production Number) Articles, books, identities, subjects (more?) System-local, a few union catalogs (narrower use) An identifier for (OCLC) Pica catalogues, used to refer to books as well as serials, people, and subjects (more?). In some areas it has been adopted to be unique throughout specific union catalogs (e.g. in the Netherlands, Germany), but not between them (as such union catalogues assign numbers separately of each other) [49]
SICI Serials  ? (NISO Z39.56): Serial identifier that is variable-length and contains information whether the serial is electronic/paper/microformat, and allows identification of derivatives. [50]
SISO classification  ? Dutch equivalent for DDC (Dewey) (derivative or equivalent?(verify)) [51]
ResearcherId Identities [52]
SuDocs, SUperintendent of DOCumentS classification system classification/subjects Tries to group government documents by authors/organization/agency/department. [53] [54] [55]
UDC (Universal Decimal Classification) classification/subjects a system that uses symbols to combine and relate concepts from Dewey. [56].

See also

...many other glossaries, including:

Further library related notes

Call numbers

This article/section is a stub — probably a pile of half-sorted notes, is not well-checked so may have incorrect bits. (Feel free to ignore, fix, or tell me)

The call number is the thing on the spine of the book.

A call number is like an address that locates an item in a particular library - or set of libraries when libraries join, grow, have per-department libraries in universities, or such.

Call numbers often consist of a categorization code (e.g. Dewey, LCC, or something more local), combined with something that makes the number unique. Cutter numbers are not unusual to see.

See also e.g.:

More than call numbers

This article/section is a stub — probably a pile of half-sorted notes, is not well-checked so may have incorrect bits. (Feel free to ignore, fix, or tell me)

The numbering/identifying in a library may be more complex than just call numbers. Consider that:

  • A call number really identifies a location rather than an exemplar. A library may have multiple copies of something (e.g for popular things), and it may have something in various locations (e.g. in multiple department libraries). As such, there may be multiple call numbers for a single title, and multiple exemplars for a single call number.
  • a loaning system will often identify specific copies (exemplar), which is more specific than a call number

  • A specific item may be grouped in one of various ways, particularly if that group shouldn't be separated. Consider parts of an encycopedia, all journals from, say, a year, and such. Such groups may also be considered items in the looser sense, particularly in search systems.

A loaning system mostly cares to keep track of specific exemplars, while a search system may wish to try to reason at the level of work or expression, grouping different publications, releases, edits, and (arguably) translations of the same work.

It can for example be nice to see book hits grouped as "8 versions in 3 languages published between 1960 and 1976." or hits from the same journal grouped, although you need complete and correct metadata to do better than just guess at this.

Subject headings; classification

Subject headings are related to classification (and in an abstract sense are classifiers), but in the library world they are different, mostly because of not-so-subtle differences in application/rules.

Many classification systems apply just one class (partly just make call numbers useful), while many subject headings can apply to an item to provide multiple access points in a catalog for an item (particularly in digital systems where it does not mean a library card explosion), and also does not require strict exclusive semantic content of the subjects (which is generally quite preferable in classification).

Of course, digital approaches have changed and in particular fuzzied the difference -- and made it less important for people to understand how a catalog works.

Cutter numbers, Cutter Classification

This article/section is a stub — probably a pile of half-sorted notes, is not well-checked so may have incorrect bits. (Feel free to ignore, fix, or tell me)

Cutter numbers/codes usually refer to short alphanumeric (letter-number) codes used for things other than classification(verify), usually in call numbers.

They are a feature of Cutter classification that has been adopted in other systems, including LoC call numbers.

It is most often used to code author names (in a soundex-like way(verify)), and can also be used for subjects, places, titles, indication of things like translations, and more.

They are often simple transforms and may require lookup tables, as classification rules require. For example, look at LoC's cutter details.

These are often decided according to tables/rules, e.g. LoC's.

For example, in LC call number QH316.5.B56 (though more likely shown with a space, QH316.5 .B56), QH316.5 is an LCC, B56 is a Cutter number (apparently for the author).

Cutter Expansive Classification is a classification system that, at the time, was both simpler and more complete than various other systems. It looks like a simpler, more general form of LCC, which is mostly because LCC's design was inspired by cutter(verify).

(there are also translation tables that map between Cutter and Dewey, which is sometimes up to the tens sometimes up to specific Dewey codes, e.g. 730 is WC, 812 is YD)

See also:

And perhaps:

Library of Congress something somethings

The most interesting ones are:

  • LCCN, Library of Congress Control Number
  • Library of Congress call numbers (no abbreviation)
  • LCC, Library of Congress Classification
  • LCSH, Library of Congress Subject Headings

More details:


This article/section is a stub — probably a pile of half-sorted notes, is not well-checked so may have incorrect bits. (Feel free to ignore, fix, or tell me)

LCCN, Library of Congress Control Number, is used to identify:

  • bibliographic records
  • authority records (authority records are those that show the established or preferred form of names, titles, regions, terms, subjects, etc.)
  • classification records ((verify))

The identifier mainly consists of a prefix (if applicable), year digits, and a serial number assigned within that year.

The format changed in 2001. Up to 2000 (now known as Structure A) the codes could include:

  • Alphabetic Prefix
    • up to three characters (in records: often three reserved spaces, left-justified within blanks, all blanks if no prefix. Blanks can mean spaces and #)
  • Year (two-character. If you want to extract the real year from these digits, see e.g. [57])
  • Serial Number (six-digit)
  • Supplement Number - a single character. Was never used.
  • Suffix / Alphabetic Identifier (optional, variable length, and apparently now deleted)
  • Revision Date (optional, variable length)

Since Jan 2001 (Structure B) codes are only just:

  • Alphabetic Prefix (now two characters)
  • Year (now four-digit)
  • Serial Number (six-digit, as in A)

Records, screen formatting and canonicalization

Records may apply specific rules about encoding LCCNs, such as reserving fixed-length space for the prefix and filling any of those not used by prefix characters with spaces.

Screen-formatted LCCNs may

  • add a space between prefix and number leave such a space
  • may add a hyphen between year and serial
  • may abbreviate by stripping zeroes from the left of the serial number.

The following are all structurally valid enough LCCNs:

nb 71-005810/AC/r86

The most canonical form seems to be prefix, 2/4-digit year, unabbreviated serial (no zeroes stripped), with no hyphens or spaces, and all suffix information stripped (doesn't affect uniqueness anyway - it's just extra information that is also fairly rarel used). For the above examples:


See also

This is probably the handiest form to pass around - this unabbreviated-number form is what various services expect (and dashing and abbreviating should not be used in records).

Not all LCCN-related services are clever enough to (re-)canonicalize input they get, so could fail to match things you don't format for them.

Notes on prefixes

This article/section is a stub — probably a pile of half-sorted notes, is not well-checked so may have incorrect bits. (Feel free to ignore, fix, or tell me)

The alphabetic prefix consisting of one, two, or three characters (though three-character only appears in pre-2001 prefixes/LCCNs) and indicate specific series of LCCNs and/or the type of record.

For example, the gm in gm71002450 ([58]) indicates a series of maps ('...Cataloged by LC, 1968-1972'), while 71002450 does not exist ([59]). LCCNs 68001993, sa68001993, j68001993, and he68001993 point to four different records (sa: southeast asian 1961-, j: japanese 1949-, he: hebrew 1964-).

Some prefixes indicate name or subject authorities, a few are classifications. Pre-2001, most prefixes are for items/bibliographic records. Post-2001, these same prefixes are probably not used anymore, so you now see prefixes mainly on non-bibliographic records(verify). A lack of prefix usually points to item/bibliographic entries (but also holdings, community records). (verify)

Prefixes include: (verify)

  • Authority record prefixes
    • n: name/subject authorities (Library of Congress)
    • no: name/subject authorities (OCLC)
    • nr: name/subject authorities (RLIN)
    • nb: name/subject authorities (British Library)
    • sh: subject headings (Library of Congress)
    • sp: proposed subject (moved to sh if/when approved)
    • sj: "Juvenile subject authority keyed by LC and distributed in the LC Annotated Children's Cataloging Program",
  • Classification record prefixes
    • cf: classification record (Library of Congress)
    • ct: table record (Library of Congress)
  • Holdings and Community Information Record Prefixes

It seems that searches can be finicky/fragile in the face of prefixes - even LoC's own. For example, in my tests:

  • A Z39.50 search for lccn="unk81005124" yields record unk81005124 ([60]) - works
  • A Z39.50 search for lccn="81005124" yields record 81005124 ([61]) - works
  • Attempt to find he68001993 ([62])
    • A Z39.50 search for lccn="he68001993" gave no hits
    • A search for lccn="68001993" returned three records, those identified by sa68001993 ([63]), j68001993 ([64]), and he68001993 ([65])
      • ...and while the prefix-less 68001993 exists ([66]), it doesn't appear in this search

While there is probably a technical explanation for this, it seems to mean you need logic and possibly two searches to find that you want.

See also

Call numbers

Library of congress's call numbers (no abbreviation) is a call number for use in the actual library. Being a call number, it uses LoC classification, i.e. LCC, combined with some sort of item-narrowing addition. (verify)

For example, QE534.2.B64 (see also [67], where the example was taken from)

  • QE534.2 is the LCC category, apparently Earthquakes, Seismology - General Works - 1970 to Present. For details, see the notes on LCC below.
  • A next letter-number combination, if present, is a listed journals, or a cutter number (verify)

LCC (LoC Classification)

LCC, Library of Congress Classification, is a detailed and layered system that narrows ranged into more specific subjects.

More details for the QE534.2 example above:

  • Q is science
  • QB through QE are physical sciences
  • QE is Geology
  • the QE1-QE996.5 range is Geology
  • the QE500-QE639.5 range is Dynamic and Structural Geology
  • the QE521-QE545 range is Volcanoes and Earthquakes
  • the QE531-QE545 range is Earthquakes, Seismology
  • Apparently QE534.2 lies in a range for Earthquakes, Seismology - General Works - 1970 to Present

See also:

Note that there is an extension to basic LCC by NLM, mostly in QS, QT, QU, QV, QW, QX, QY, QZ, and WA through WZ.


LCSH, Library of Congress Subject Headings is a large and fairly wide-coverage thesaurus of subject headings (index terms) - and also acts as a controlled vocabulary. In relatively wide use, and has influenced other controlled keyword sets.

Subject Headings are mostly a formal name for a controlled keyword set used on items in a catalogue, that is often also searchable.

See also:


ISBNs are assigned to books, but note that paper and electronic forms of the same book may be assigned separate ISBNs.


A 10-digit ISBN is made of:

  • The Group Identifier (correlated to countries)
  • The Publisher Identifier / Registrant (ranges registered per group identifier)
  • The Title Identifier (that which is leftover, minus the check digit)
  • The Check Digit.

It is however nontrivial to correctly hyphenate an ISBN; the group identier, publisher identifier, and title identifier all vary in length depending on preceding items, and based on knowledge external to the number, not just calculation on it. To dash a given ISBN you need yo know about the identifiers used in it (group identifiers, and all regestered publisher identifiers for each group identifier; the length of the title identifier is simply the rest).

See e.g. the references below.

A 13-digit ISBN is part of EAN. Currently, they are ISBN10s placed in a single pseudo-country (978, 'bookland'), and other than prepending that number have the same items (although its check digit is calculated in a different way).

EANs are not hyphenated(verify), but ISBN13s typically are, by adding a hyphen after the three-digit country code, and following the ISBN10 rules for the rest. ( least in theory; I've seen a few books hyphenating the two differently).


As just mentioned, thirteen-digit ISBNs are EAN codes.

The EAN form has been used for a while in barcodes.

Since 2007, ISBN have been required to be in ISBN13 form.

An EAN containing an ISBN is occasionally referred to as an ISBN13, while ten-digit ISBNs are occasionally retro-named ISBN10s for contrast.

The current EAN ISBNs are said to be in 'Bookland' (978), as EANs must contain a country reference (GS1 prefix). This means that all current EAN/ISBN13s are simply the ISBN10 with 978 prepended and with its check digit (which is also in the last position in EANs) recalculated using the EAN method instead of the ISBN method.

This also implies that ISBN13s starting with 978 also have an equivalent ISBN10 form that you can easily convert between - add/chop off the three bookland digits, recalculating the check digit in the proper way.

The move to EAN is also an expansion: The 979 block has already been allocated for future use, and others may follow (though 979 will probably be enough for a while).

Cover images, relations, etc.

The easiest way to get images is to hotlink to amazon, which allows it under some relatively loose conditions. See also Amazon_notes#Images.

Since covers can be US-centric or country-centric, it can pay to get images from different amazon collections. It can also be useful to find a book site in you country, both for better-matching images and for better coverage (For example, the Dutch has more images for Dutch books than Amazon does).

Sites such as ISBNdb can be useful for per-book cross-linking portal purposes.

You can looj up alternative additions with things like OCLC's xISBN, or LibraryThing's thingISBN API or data.

Wikipedia has a whole list of site options of things to do with ISBNs.

See also



Data for hyphenation:

Further details and links:


There are a few potentially interesting sources to look up ISBNs for shopping, reviews, information and more:


Shop search:

Information and 2.0ness:

Others suggestions:

  • Ottobib: format citation as MLA, APA format, etc.


Internationally standardized with ISO 3297.

Used for periodicals, print or electronic.

Note that any periodical may exist in one form, or both, and if both exist, they often have separate ISSNs for the version in print and the electronic version, and 'eISSN' (and sometimes 'ESSN') is sometimes used to refer to the electronic version. In these cases, the pair of ISSNs should perhaps be seen as practically equivalent.


This article/section is a stub — probably a pile of half-sorted notes, is not well-checked so may have incorrect bits. (Feel free to ignore, fix, or tell me)

Abbreviations of serial/journal names vary a bit in practive.

That is to say, different institutions abbreviate different ways, mainly in terms of specific abbreviations of words/phrases, and when being picky, also in the usage of punctuation. Different methods/sources of abbreviations are trusted to different degrees in different areas.

The standard way of abbreviation seems to be defined in ISO 4

See also:


DOI is meant to identify pieces of itellectual property.

In a DOI code, for example 10.1000/abc...

  • the 10 designates a DOI, which is just one implementation of the CNRI Handle system; other Handle systems use other prefixes.
  • The rest of the code before the slash is the DOI registrant prefix, 1000 in the example above. You can buy such a prefix from a Registration Agency (or possibly an experimental one from the International DOI Foundation(verify).
  • ...followed by by item identifiers assigned by that registrant. Can be anything. (The combintion will always be unique, as the the registrant prefix acts as a namespace)

The combination is like an URN (e.g. 10.1000/abc) in that it identifies but does not locate. You need a DOI resolver to look it up to what it refers to, and get a copy available to you. An URL containing a DOI is often a combination of resolver and DOI indentifier, that may work (only) for a specific institution.

DOI syntax is defined in ANSI/NISO Z39.84 [68].

See also:


This article/section is a stub — probably a pile of half-sorted notes, is not well-checked so may have incorrect bits. (Feel free to ignore, fix, or tell me)

PPN and Worldcat:

You can search for Dutch PPNs in Worldcat like:

Doesn't seem to work from the search API(verify)

Identities (via name, plus PPN as disambiguation?) to:

...which uses:

...which I can't find anything about.

(GGC being the Gemeenschappelijk Geautomatiseerd Catalogiseersysteem[69])


On what various common identifiers really are, and what that means to mapping between them

This article/section is a stub — probably a pile of half-sorted notes, is not well-checked so may have incorrect bits. (Feel free to ignore, fix, or tell me)

MARC field 035 (Local System Number) will often store a (bracketed) string identifier to disambiguate the type of identifier stored there, including:

You might for example see 035 $a(OCoLC)ocm69983298

When OCLC numbers are used in the MARC field 001(verify), they are prefixed using:

  • ocm for eight-digit numbers (≤99999999)
  • ocn for nine-digit numbers (≥100000000)


  • Teoma


ISO 20775 - Holdings schema/metadata Closed, so unlikely to be used in modern open systems (verify)

AACR2 Abbreviation listing [70]