Electronic location and access (MARC 856 field) – locate resource
Most commonly used subfields:
Subfield $u = uniform resource identifier (URI)
suffices for most Web resources; do not add institution-specific URLS to OCLC master records
Subfield $z = public note – think local!
do not add institution-specific notes in OCLC master records
Subfield $3 = materials specified note
May serve as active hyperlink from catalog to the online resource in Web-based catalogs