====== 856 Electronic Location and Access (O;R) ======
 

==== Field Definition and Scope ====

This field contains the information required to locate an electronic item. The information identifies the electronic location containing the item or from which it is available. It also contains information to retrieve the item by the access method identified in the first indicator position.


==== Application of Content Designators ====

=== Indicators ===
\\
**Indicator 1: undefined (blank)** 

**Indicator 2:** none

=== Subfields ===
**$e Nonpublic note (O;NR)**\\
This note is visible only in the tagged display of the record.

**$g Uniform Resource Name (O;NR)**\\
The URN, which provides a globally unique location independent identifier.

**$n Plain name of host as given in $a (O;NR)**\\
e.g. Consortium of European Research Libraries, London

**$u Uniform Resource Locator (O;NR)**\\
The Uniform Resource Locator (URL), which provides electronic access data in a standard syntax.
Instead of the URL leading up to the online resource you may file here the URL of the resolution service for the URN given in $g. In this case the URN is to be repeated as last part of the URL.

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

**$z Public note (O;R)**\\
Please use English language for this note.

==== Input Conventions ====

see also [[956]].

==== Examples ====
<code>
 1. 856 ##$nUnion catalogue of Swedish libraries$uhttp://websok.libris.kb.se
          /websearch/search?SEARCH_NUMM=7665205$8eng$zBibliographic record
</code>


==== Internal Representation ====
<code javascript>
{"data": {"extResource": [{
    "display": "Display text ($n)",
    "note": [{
        "text": "Public note ($z)",
        "lang": "Language code ($8)"
    }],
    "url": "URL ($u)",
    "urn": "URN ($g)",
    "remark": "Non-Public note ($e)"
}]}}
</code>


==== Change History ====
  * //17.07.2017//: First indicator position values will no longer be supported once the CT has been migrated into its new environment.
  * //17.07.2017//: Subfields $1, $6, $a, $h and $y will no longer be supported once the CT has been migrated inot its new environment. Any content of subfield $a will be mapped to subfield $n during ingest if no subfield $n is present.
  * //17.07.2017//: Subfields $e, $g, $n and $u are no longer repeatable, once the CT has been migrated into its new environment.
  * //17.07.2017//: New subfield $8 has been added.