956 Remote access to external systems (O;R)

This field holds the essential data that are necessary to trigger a retrieval operation in an external database system. The aim is to provide further information related to the described entity, which is out of scope of the CERL Thesaurus such as sample bibliographic records or provenance information.

Indicator 1: undefined (blank)

Indicator 2: Specifies the type of information retrieved in the external system:

• 0 sample bibliographic record
• 1 provenance information
• 2 information about the described entity
• 3 depiction
• 8 other record for the same entity (owl:sameAs) ¹⁾
• 9 other ²⁾

$0 Type of Resource (M;NR)
A four character code indicating the type of the external dataset this field links to. Currently, the following values are supported:

$c Rights statement (O;NR)
A statement on the copyrights, licenses etc. Particularly in regard to portraits etc. It consists of the name of the right holder, the License / Copyright status and and URL (to the page where the item and its license is described (e.g. Wikimedia Commons), each separated by two dashes, preceded and followed by a blank ( – ). If the rights holder requests any specific text to idicate the license, use this instead of their name. If this prescribed text refers to either or both the license by its official name or acronym and the URL of a resource describing item and license, one or both of the other parts of this statement can be omitted (see below for an example)

$n System Code (M;NR)
A four character alphanumeric code identifying the target system. Currently the following codes are supported:

$y Search term (M;NR)
A search term used to retrieve the wanted records in the remote system

$8 Language Code (O;R)
Must precede any subfield $z. See the description of numerical subfields.

$z Public note (O;R)
Text to be displayed as a link in the CT web front-end.

The technique used to access the remote system is a JavaScript-based creation of a HTTP-Get request or an automated submitting of an HTML form (HTTP-Post). Each system code given in $n corresponds to a particular request algorithm within the CT web interface. Therefore codes other than on the List of System Query Codes must not be used without prior consultation with the Data Conversion Group.

Indicator position 2 can be left blank when this field is entered manually.

  1. 956  1$0prov$nGOES$zProvenance Information$u365984574
  2. 956  3$0dpct$nLINK$yhttps://upload.wikimedia.org/wikipedia/commons/4/47/PhilippMelanchthon.jpg
           $cPublic Domain -- https://commons.wikimedia.org/wiki/File:PhilippMelanchthon.jpg$8eng
           $zLucas Cranach the Elder, Portrait of Philipp Melanchthon, 1543
  3. 956  3$0dpct$nLINK$yhttps://upload.wikimedia.org/wikipedia/commons/f/f6/Hannover_Skyline.jpg$8ger
           $zSkyline von Hannover$cThis Wikipedia and Wikimedia Commons image is from the user Chris 73 and is 
           freely available at http://commons.wikimedia.org/wiki/File:Hannover_Skyline.jpg under the creative 
           commons cc-by-sa 3.0 license.
  4. 956  8$0same$nWDAT$yhttp://www.wikidata.org/entity/Q55848552$8eng$zWikidata description set

{"data": {"extDataset": [{
    "typeOfResource": "Type of Resource ($0)",
    "code": "System query code ($n)",
    "searchTerm": "Search Term ($y)",
    "rights": "License statement ($c)",
    "note": [{
        "text": "Public note ($z)",
        "lang": "Language code ($8)"
    }]
}]}}

• 17.07.2017: First indicator position becomes obsolete once the CT has been migrated into its new environment
• 17.07.2017: Subfields $6 and $u will no longer be supported, once the CT has been migrated into its new environment. Any subfield $u will be mapped to $y during ingest.
• 17.07.2017: Added new subfield $8.
• 17.07.2017: Removed experimental subfield $0 from format description
• 17.07.2017: Added new subfield $0 to format description.
• 09.08.2017: Added new subfield $c
• 23.01.2019: Added list of codes used in subfield $n.