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Uniform Resource Identifiers (URI) for National Diet Library resources

Resources created by the National Diet Library (NDL) are identified by Uniform Resource Identifiers (URI), which can be used either to access the resource itself or to link it to other resources on the World Wide Web via HTTP protocol. To maintain stability and continuity, URIs comprise a fixed domain and path. Accessing a URI also provides users with additional information relevant to the resource.

Bibliographic data

NDL Bibliographic ID (NDLBibID)

Explanation NDLBibID refers to identifiers given by the NDL to bibliographic data created by the NDL.
Modification or deletion of the associated resource Although bibliographic data is subject to update, NDLBibIDs and their associated library materials do not change. If bibliographic data is deleted, however, its associated NDLBibID is no longer valid.
Domain/path http://id.ndl.go.jp/bib/
Examples of URI containing the ID
  1. Kokuritsu kokkai toshokan geppo = National Diet Library monthly bulletin
    http://id.ndl.go.jp/bib/000000008550
  2. Guang yun jiao lu (Huang kan wen ji)
    http://id.ndl.go.jp/bib/a1000068044
  3. Kokuritsu kokkai toshokan geppo nenkan sakuin
    http://id.ndl.go.jp/bib/4108438
Number of IDs in use Approx. 25.4 million (as of March 2019)
Referent Bibliographic records of library materials cataloged in the NDL Online
Availability
  1. NDLBibIDs in the following format are included in metadata that can be retrieved from the NDL Search via API:
    <rdfs:seeAlso rdf:resource="http://id.ndl.go.jp/bib/xxxxxxxxx"/>
    The API supports OAI-PMH, SRU, OpenSearch, and other protocols.
  2. NDLBibIDs are included in the following open datasets:

IDs assigned to metadata of digital contents (NDL Metadata ID)

Explanation The term "NDL Metadata ID" refers to identifiers given by the NDL to metadata of digital contents in the NDL Digital Collections.
Modification or deletion of the associated resource Although metadata is subject to update, NDL Metadata IDs do not change.
Domain/path http://id.ndl.go.jp/digimeta/
Examples of URI containing the ID Kokuritsu kokkai toshokan nenpo = Annual report of the National Diet Library. 1953
http://id.ndl.go.jp/digimeta/3048007
Number of IDs in use Approx. 3.9 million (as of March 2019)
Referent Bibliographic records of library materials cataloged in the NDL Online
Availability NDL Metadata IDs in the following format are included in metadata that can be retrieved from the NDL Search via API:
<rdfs:seeAlso rdf:resource="http://id.ndl.go.jp/digimeta/xxxxxxx"/>
The API supports OAI-PMH, SRU, and other protocols.

National Bibliography Number (JPNO)

Explanation JPNO refers to identifiers given by the NDL to bibliographic data of materials included in the Japanese National Bibliography.*
Modification or deletion of the associated resource Although bibliographic data is subject to update, JPNOs and their associated library materials do not change. If bibliographic data is deleted, however, its associated JPNO is no longer valid.
Domain/path http://id.ndl.go.jp/jpno/
Examples of URI containing the ID Kokuritsu kokkai toshokan geppo = National Diet Library monthly bulletin
http://id.ndl.go.jp/jpno/00008614
Number of IDs in use Approx. 6.2 million (as of March 2019)
Referent NDL Search results
Availability
  1. JPNOs in the following format are included in metadata that can be retrieved from the NDL Search via API:
    <rdfs:seeAlso rdf:resource="http://id.ndl.go.jp/jpno/xxxxxxxx"/>
    The API supports OAI-PMH, SRU, and other protocols.
  2. JPNOs are included in the open dataset Bibliographic ID List (tsv format)

* Includes all domestic publications submitted under the Legal Deposit System and those acquired through donation, purchase, or other means as well as foreign publications in the Japanese language. The NDL gives e-books and e-journals in the National Bibliography NDL Persistent IDs (info:ndljp) instead of JPNO IDs.

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Authority data

The following three identifiers are given to authority data. For further information on the URI of authority data, please also refer to 2. URI Links under Description of Functions in the Web NDL Authorities.

NDL Authority Data ID: personal name/family name/corporate body name

Explanation NDL gives Authority Data IDs to authority information for personal names, family names, and corporate body names. Every authority data is associated with two types of URI: an Authority Information URI embedding an Authority Data ID and a Name Entity URI.
Modification or deletion of the associated resource Although authority information and headings are subject to update, Authority Data IDs do not change. If the authority information is deleted, however, its associated Authority Data ID is no longer valid.
Domain/path
  1. Authority Information URI: http://id.ndl.go.jp/auth/ndlna/
  2. Name Entity URI: http://id.ndl.go.jp/auth/entity/
Examples of URI containing the ID Natsume Soseki
  1. Authority Information URI: http://id.ndl.go.jp/auth/ndlna/00054222
  2. Name Entity URI: http://id.ndl.go.jp/auth/entity/00054222
Number of IDs in use Approx. 1.1 million (as of March 2019)
Referent Web NDL Authorities data
Availability
  1. Authority Information URIs in the following format are included in metadata provided via the Web NDL Authorities:
    • Authority Information URI: <skos:Concept rdf:about="http://id.ndl.go.jp/auth/ndlna/xxxxxxxx">
    • Name Entity URI: <foaf:Person rdf:about="http://id.ndl.go.jp/auth/entity/xxxxxxxx">
  2. Name Entity URIs in the following format are included in metadata that can be retrieved from the NDL Search via API:
    <foaf:Agent rdf:about="http://id.ndl.go.jp/auth/entity/xxxxxxxx">
    The API supports OAI-PMH, SRU, and other protocols.

NDL Authority Data ID: geographic name/uniform name

Explanation NDL gives Authority Data IDs to authority information for geographic names and uniform names.
Modification or deletion of the associated resource Although authority data and headings are subject to update, Authority Data IDs do not change. If the authority data is deleted, however, its associated Authority Data ID is no longer valid.
Domain/path http://id.ndl.go.jp/auth/ndlna
Examples of URI containing the ID Genji monogatari
http://id.ndl.go.jp/auth/ndlna/00633493
Number of IDs in use 37,984 (as of March 2019)
Referent Detailed information page of the Web NDL Authorities
Availability
  1. Authority Data IDs in the following format are included in metadata provided via the Web NDL Authorities: <skos:Concept rdf:about="http://id.ndl.go.jp/auth/ndlna/xxxxxxxx">
  2. Authority Data IDs in the following format are included in metadata that can be retrieved from the NDL Search via API: <dcterms:subject rdf:Description rdf:about="http://id.ndl.go.jp/auth/ndlna/xxxxxxxx">
    The API supports OAI-PMH, SRU, OpenSearch, and other protocols.

NDL Authority Data ID: NDLSH (topical term/subdivision)

Explanation NDL gives Authority Data IDs to authority information for topical terms. Every authority data for topical terms is associated with two types of URI: an Authority Information URI embedding an Authority Data ID and an Authority Information URI embedding a label (literal of the topical term).
Modification or deletion of the associated resource Although authority data and headings are subject to update, Authority Data IDs do not change. If the authority data is deleted, however, its associated Authority Data ID is no longer valid.
Domain/path http://id.ndl.go.jp/auth/ndlsh/
Examples of URI containing the ID Internet
Number of IDs in use 127,840 (as of March 2019)
Referent Detailed information page of the Web NDL Authorities
Availability
  1. Authority Information URIs in the following format are included in metadata provided via the Web NDL Authorities:
    • Authority Information URI embedding an Authority Data ID: <skos:Concept rdf:about="http://id.ndl.go.jp/auth/ndlsh/xxxxxxxx">
    • Authority Information URI embedding a label: <owl:sameAs rdf:resource="http://id.ndl.go.jp/auth/ndlsh/xxxxx"/>
  2. Authority Information URIs embedding an Authority Data ID in the following format are included in metadata that can be retrieved from the NDL Search via API:
    <dcterms:subject rdf:Description rdf:about="http://id.ndl.go.jp/auth/ndlsh/xxxxxxxx">
    The API supports OAI-PMH, SRU, OpenSearch, and other protocols.

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Digital content (digitized materials, online resources, etc.)

NDL Persistent ID (info:ndljp/pid)

Explanation The term "NDL Persistent ID" refers to identifiers given by the NDL to digital content in the NDL Digital Collections or collected via the Web ARchiving Project (WARP) .
Modification or deletion of the associated resource Although the image and its metadata are subject to modification, the ID does not change.
Domain/path Digital content in the NDL Digital Collections:
  • http://dl.ndl.go.jp/info:ndljp/pid/
Digital content collected by WARP
  • http://warp.da.ndl.go.jp/info:ndljp/pid/
Examples of URI containing the ID Digital content in the NDL Digital Collections Digital content collected by WARP
Number of IDs in use Digital content in the NDL Digital Collections
  • Approx. 3.9 million (as of March 2019)
Digital content collected by WARP
  • Approx. 7.3 billion (as of March 2019)
Referent Digital content in the NDL Digital Collections
  • NDL Digital Collections content viewer
Digital content collected by WARP
  • Files which comprise websites displayed by WARP
Availability Digital content in the NDL Digital Collections
  • NDL Persistent IDs in the following format are included in metadata provided via the NDL Search and retrievable via API.
    <dcterms:identifier rdf:datatype="http://ndl.go.jp/dcndl/terms/NDLJP">info:ndljp/pid/xxxxxxxx</dcterms:identifier>
    <rdfs:seeAlso rdf:resource="http://dl.ndl.go.jp/info:ndljp/pid/xxxxxxxx"/>
    The API supports OAI-PMH, SRU, and other protocols.
  • Persistent IDs in the following format are included in the open dataset Bibliographic Data of the National Diet Library Digital Collections (xlsx and tsv format): <URL: http://dl.ndl.go.jp/info:ndljp/pid/xxxxxxx>

Reference: Digital Object Identifier (JaLC DOI)

JaLC DOI are managed by Japan Link Center. Please also refer to Assignment of a DOI name to an object by NDL.

Explanation The term "DOI" refers to identifiers given to digitized versions of NDL holdings included in the NDL Digital Collections and NDL publications. The ID consists of the NDL's prefix (10.11501) followed by a slash and the numeric portion of the NDL Persistent ID.
Modification or deletion of the associated resource Objects are not to be deleted.
Domain/path http://doi.org/
Examples of URI containing the ID Kokuritsu kokkai toshokan nenpo = Annual report of the National Diet Library. 1953
Number of IDs in use 2.5 million (as of March 2019)
Referent NDL Digital Collections content viewer
Availability DOIs in the following format are included in metadata provided via the NDL Search and retrievable via API.
<dcterms:identifier rdf:datatype="http://ndl.go.jp/dcndl/terms/DOI">10.11501/xxxxxxx</dcterms:identifier>
<rdfs:seeAlso rdf:resource="http://dx.doi.org/10.11501/xxxxxxx"/>
The API supports OAI-PMH, SRU, and other protocols.

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Contact for inquiries about URIs for NDL resources

Standardization Section, Digital Information Distribution Division,
Digital Information Department, National Diet Library
E-mail: standardizationat n d l dot g o dot j p

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