Very nice, thanks.
I wonder the rationale behind searching both valid and cancelled LCCNs.
This has caused me trouble in the past in similar systems, because a
cancelled LCCN seems in some cases to duplicate a different valid LCCN,
so you search on an LCCN, and get, in this case, both the correct record
and and an incorrect record -- the requirement that software take
account of this and look into the records to see which is the valid one
adds significant complexity to the software, and is also a detail likely
to be overlooked in client software implementation.
I wonder if any alternatives were considered. I'm not exactly sure what
the solution is though -- if it wasn't for the _collision_ issue, then
we could say requesting a permalink for a cancelled LCCN should result
in an HTTP redirect to the permalink for the correct LCCN. But a
cancelled LCCN on one record can be identical to a correct LCCN on
another, or theoretically the same cancelled LCCN could exist on more
than one record -- making it unclear what design could be better.
On 9/7/2011 1:55 PM, Della Porta, Ann wrote:
Apologies for cross posting.
The Library of Congress is pleased to announce an expansion of its LCCN Permalink
Service for the Library's name and subject authority records. These persistent URLs
are based on the Library of Congress Control Number (LCCN). As with bibliographic
records, LCCN Permalinks are displayed on authority record entries in LC
Authorities<http://authorities.loc.gov>.
Create an LCCN Permalink
Simply begin your URL with the LCCN Permalink domain name --
http://lccn.loc.gov/ -- then add an LCCN.
Examples: http://lccn.loc.gov/n79018774 or
http://lccn.loc.gov/sh85026371
LCCNs should be formatted according to the
info:lccn<http://info-uri.info/registry/OAIHandler?verb=GetRecord&metadataPrefix=reg&identifier=info:lccn/>
URI specification. Instructions are also available in the LCCN Permalink
FAQ<http://lccn.loc.gov/lccnperm-faq.html>.
How LCCN Permalink Works
An LCCN Permalink retrieves a MARCXML-formatted record using the Z39.50/SRU protocol. Both valid and
cancelled LCCNs (MARC 21 fields 010a and 010z) are searched. Authority record displays for LCCN
Permalink follow the labeled display found in LC Authorities. MARCXML and MADS versions of the records
are also available. Displays link to entries in LC Authorities<http://authorities.loc.gov> and
the LC Online Catalog<http://catalog.loc.gov> -- and, where appropriate, to entries in the
Virtual International Authority File<http://viaf.org> and LC Authorities and
Vocabularies<http://id.loc.gov/>.
More Information
Additional information on this service is available on the LCCN Permalink
FAQ<http://lccn.loc.gov/lccnperm-faq.html>. Specific questions can also be sent to
the Library of Congress through
Ask-A-Librarian<http://www.loc.gov/rr/askalib/ask-digital.html>.
Ann Della Porta
Chief, Integrated Library System Program Office
Library of Congress
Washington, DC 20540-4010
[email protected]
