Authority Cluster Resource

The VIAF Authority Cluster endpoint provides identification of name authority entities, access to their data representations and convenience functions for translation lookups from origin IDs as well as seach/browse access.

URLs and Supported Requests

The Authority Cluster Resource supports these operations:

Operation Resource URL HTTP METHOD Response
Identify{VIAF_Identifier} GET Redirect (303)
Get Data{VIAF_Identifier}/ GET Data
Get Data in Format{VIAF_Identifier}/{Record_Format} GET Data
Translate LCCN ID to VIAF URI{Library_of_Congress_Controll_Number} GET Redirect (301)
Translate Source ID to VIAF URI{Authority_Source_Code}|{Local_Authority_ID} GET Redirect (301)
SRU Search{CQL_Query}&maximumRecords=10&startRecord=1&sortKeys=holdingscount&httpAccept=text/xml GET Data
SRU Browse{CQL_Query}&responsePosition=10&maximumTerms=20 GET Data
Auto Suggest{Search_Terms}&callback={Optional_Callback_Name} GET Data

Response Formats

The VIAF Authority Cluster returns a mixture of of data responses and HTTP redirect responses.

Redirect Responses

Returns an HTTP 303 redirect response. This is the URI that stands for the real-world thing its corresponding data responses will describe. See the Example URLs section below for further explanation.
Translate Library of Congress Control Number to VIAF URI
Returns an HTTP 301 redirect response. This is is used so that clients who know the LCCN identifier to resolve the corresponding VIAF URI.
Translate Source ID to VIAF URI
Returns an HTTP 301 redirect response. This is is used so that clients who know the identifier used by contributing authority file to resolve the corresponding VIAF URI.

Data Responses

The Authority Cluster endpoint allows a client to specify the response format either through content negotiation or by using a URL suffix.

Response Format Content Negotiation mime type
Use with HTTP accept header
Examples Specifying the Response Format By URL




Note the trailing slash that distinguishes the data response from the identfication URI.

VIAF XML application/xml
JSON application/json
JSON LD application/ld+json
RDF XML application/rdf+xml
RSS XML application/rss+xml








Data responses can take a callback parameter to allow clients to retrieve JSON-P output.

SRU Search and Browse Responses

Response Format Content Negotiation mime type
Use with HTTP accept header
httpAccept Parameter Value(s)
HTML (default)







RSS application/rss+xml application/rss+xml






Translating Source Control Numbers to VIAF URIs

Local control numbers from the authority data sets can be translated to the corresponding VIAF URIs using an authority source code and the local identifier.

Authority Source Codes

Source Code Authority
ALL All source data within VIAF
BAV Biblioteca Apostolica Vaticana
BLBNB National Library of Brazil
BNC National Library of Catalonia
BNCHL National Library of Chile
BNE Biblioteca Nacional de España
BNF Bibliothèque Nationale de France
BNL National Library of Luxembourg
B2Q National Library and Archives of Quèbec
CYT National Central Library, Taiwan
DBC DBC (Danish Bibliographic Center)
DNB Deutsche Nationalbibliothek
EGAXA Bibliotheca Alexandrina (Egypt)
ERRR National Library of Estonia
ICCU Istituto Centrale per il Catalogo Unico
JPG Getty Research Institute
KRNLK National Library of Korea
LC Library of Congress/NACO
LAC Library and Archives Canada
LNB National Library of Latvia
LNL Lebanese National Library
MRBNR National Library of Morocco
NDL National Diet Library, Japan
NII National Institute of Informatics (Japan)
NKC National Library of the Czech Republic
NLA National Library of Australia
NLB National Library Board, Singapore
NLI National Library of Israel
NLIara National Library of Israel (Arabic)
NLIcyr National Library of Israel (Cyrillic)
NLIheb National Library of Israel (Hebrew)
NLIlat National Library of Israel (Latin)
NLP National Library of Poland
NLR National Library of Russia
NSK National and University Library in Zagreb
NSZL National Szèchènyi Library, Hungary
NTA National Library of the Netherlands
NUKAT NUKAT Center of Warsaw University Library
N6I National Library of Ireland
PTBNP Biblioteca Nacional de Portugal
RERO RERO.Library Network of Western Switzerland
SELIBR National Library of Sweden
SRP Syriac Reference Portal
SUDOC Sudoc [ABES], France
SWNL Swiss National Library
UIY National and University Library of Iceland (NULI)
VLACC Flemish Public Libraries
WKP Wikidata
W2Z National Library of Norway
xA (eXtended Authorities)
XR xR (eXtended Relationships)

SRU Searching and Browsing

Search Parameters

Parameter Required? Description
Expected/Sample Value
query Yes CQL query query=cql.any+%3D+%22Jane+Austen%22
httpAccept No The accept type to return the results as. By default html is returned

Response format values:

  • text/xml
  • application/xml
  • application/rss+xml
  • application/xhtml+xml
  • text/html
recordSchema No The record schema to return information in. By default VIAF XML is returned

Record schema values:

  • info:srw/schema/1/marcxml-v1.1
  • info:srw/schema/1/unimarc-v0.1
  • info:srw/schema/1/JSON
maximumRecords No

The number of records to return per page.

The maximum records which can be returned depends on the recordSchema.

  • Only 10 VIAF Cluster records can be returned.
  • 250 of any other type records can be returned.

default Full VIAF Cluster records - 10

default all other types of records - 100

startRecord No The record to start with startRecord=1 
sortKey No

Modifies the search response to be ordered by WorldCat holdings count.

Presently, the only explicit sort option is holdings count. If the sortKey parameter is omitted, the default order will be the reverse order of loading.

Sort key values:

  • holdingscount


callback No JSONP Callback function name  

Browse Parameters

Parameter Required? Description
Expected/Sample Value
scanClause Yes CQL query query=cql.any+%3D+%22Jane+Austen%22
maximumTerms No The number of items per page to include in the response. Similar to the maximum records parameter in the search response.
responsePosition No

The value for this parameter will put the seed term (or closest match) at the specified position.

For example, if the API request includes the following parameters:


the closest match to the personal name "wittgenstein" will be at position 10 response and there will be 10 terms preceeding it and 9 after it in the list of 20.

callback No JSONP Callback function name  

The Contextual Query Language (CQL) Indices

A list of possible indices to be used in Search and SRU Search requests. You can browse values for each search term by going to, selecting the index term on the right side of the page, entering a term, and pressing the "Browse" button.

Note that search terms can be:

  • = (one or more terms)
  • exact (search the exact string, including any punctuation)
  • any (for any of a list of terms)
  • all (for all the listed terms)
  • <
  • >
  • <=
  • >=
  • not
Index Description Expected/Sample Value(s)
cql.any All Fields cql.any+%3D+%22oclc%22
cql.serverChoice The server chooses which index to search using this value. cql.serverChoice+%3D+%22OCLC%22
local.corporateNames Corporate Names within the authority record. 110, 410, 510
local.geographicNames Geographic Names (only jurisdictional names so far) local.geographicNames+%3D+%22Dublin%22
local.LCCN Library of Congress Number (about) local.LCCN+exact+%22n2001-50284%22
local.mainHeadingEl Preferred Name - names which are the preferred form in an authority record. 1xx local.mainHeadingEl+exact+"Diana%2C+Princess+of"
local.names Names - any name preferred or alternate 1xx, 4xx, 5xx local.names+%3D+"Existentialism"
local.personalNames Personal Names within the authority record. 100, 400, 500 local.names+all+"Kierkegaard"
local.source Source Record local.source+%3D+"telephone"
local.sources Source Authority File

Source codes:

  • viaf = All VIAF
  • nla = Australia
  • vlacc = Belgium (Flemish)
  • lac = Canada
  • nkc = Czech
  • egaxa = Egypt
  • bnf = France (BnF)
  • sudoc = France (Sudoc)
  • dnb = Germany
  • jpg = Getty (ULAN)
  • nszl = Hungary
  • nliara nlilat nlicyr nliheb = Israel
  • iccu = Italy
  • lc = Library of Congress (NACO)
  • bibsys = Norway (BIBSYS)
  • nukat = Poland
  • ptbnp = Portugal
  • bne = Spain
  • selibr = Sweden
  • swnl = Swiss (National Library)
  • rero = Swiss (RERO)
  • rsl = Russia
  • bav = Vatican
  • xa = xA


local.title Title local.title+%3D+"impressionism"
local.uniformTitleExpressions Uniform Titles (Expressions) local.uniformTitleExpressions+all+"Magic Flute"
local.uniformTitleWorks Uniform Titles (Works) local.uniformTitleWorks+all+"Magic Flute"


Authority Cluster autosuggest functionality provides a fast lookup and clients may pass a callback function name to wrap the response in a JSONP-style method call.

Request Forms


Parameter Required? Description
query Yes The text to be queried against AutoSuggest. Use quotation marks if it contains spaces
callback No The JSONP callback function name to wrap the response data.

Example URLs

Redirect examples

Redirect responses do not return data directly. The following examples display the HTTP header response information.

Request to identify Jane Austin


HTTP/1.1 303 See Other
Server: Apache-Coyote/1.1
Location: 88615663/
Content-Type: text/plain
Content-Length: 20
Date: Mon, 07 Jul 2014 18:36:58 GMT
See Other: 102333412/

The Identify response follows the Linked Data pattern that separates the URI that identifies a real world entity from the URI for the corresponding data description about that entity. The Identify response indicates that a client should redirect or make a subsequent request to the data response it returns.

Translate Library of Congress Control Number 79032879 to VIAF URI


HTTP/1.1 301 Moved Permanently
Server: Apache-Coyote/1.1
Content-Type: application/redirect+xml
Content-Length: 0
Date: Fri, 11 Jul 2014 15:48:00 GMT

Translate Germany National Library (Deutsche Nationalbibliothek) source ID 1034425390 to VIAF URI


HTTP/1.1 301 Moved Permanently
Server: Apache-Coyote/1.1
Content-Type: application/redirect+xml
Content-Length: 0
Date: Fri, 11 Jul 2014 16:35:39 GMT

Data Examples

Return a VIAF XML record for VIAF identifier 102333412:


Return an RDFXML record for the VIAF identifier 102333412:


Returns a marc21 xml record for VIAF identifier 102333412:


SRU Search Examples

Search for records where the authority includes the terms "Jane+Austen" and return RSS:


Search for records where the authority includes the terms "Jane+Austen" and return records as SRU/XML:


Search for corporate term "OCLC":


Search for name "George" in Australia (nla) only:


SRU Browse Examples

Browse for term "OCLC":


Browse for term "OCLC" with the server identifying the index to use:


Browse for corporate term "OCLC":


Browse for geographic name "Dublin":


Browse for LCCN "n2001-50284":


Browse for "Diana, Princess of":


Browse for "Existentialism":


Browse for "Kierkegaard":


Browse for "telephone":


Browse for titles containing "impressionism":


Auto Suggest Example

Get AutoSuggested records for the term "austen":


Merging of Clusters

Authority clusters can be merged together over time as additional data is received and algorithms are updated. When an authority cluster is merged into another the client will receive an HTTP 301 redirect to the new cluster URI.

VIAF Self Documenting Features

The Virtual International Authority File links national authority files, such as the German National Library and Library of Congress, to a single virtual authority file. See VIAF at a Glance for an overview. The VIAF service is self documenting:

Documentation Endpoint Description Overview; list of participating institutions. Data source description. Search/Retrieve via URL (SRU) search parameters for cluster records.