Dear David, I believe they're codes for universities. UCSC is probably Univ of Calif Santa Cruz. UOM is University of Michigan. (You'll see STANFORD and OCLC in the results also, though OCLC is not a university). I tracked one of items in the ATOM feed to the UM record: http://mirlyn.lib.umich.edu/Record/000680081/Details#tabs The ID you see in the ATOM feed is buried in one of the 974 fields of the UM MARC record. HTH, Kevin ________________________________________ From: Code for Libraries [[log in to unmask]] On Behalf Of David Kane [[log in to unmask]] Sent: Monday, July 19, 2010 12:55 PM To: [log in to unmask] Subject: [CODE4LIB] dc:identifier in Google XML HI All, I am getting data from google books that I do not understand in the dc:identifier field. I understand ISBN: ISSN: LCCN: OCLC: but UOM:, and UCSC:? Can anyone help with what these two mean. Are they Universities? Here is a snippet of xml; <dc:format>book</dc:format> <dc:identifier>r0xMAAAAMAAJ</dc:identifier> <dc:identifier>UOM:39015035700759</dc:identifier> <dc:subject>Medical</dc:subject> <dc:title>Abstracts [of the] annual meeting</dc:title> ... generated from this URL: http://www.google.com/books/feeds/volumes?q=Abstracts%20of%20the%20annual%20meeting Thanks, David. -- David Kane, MLIS. Systems Librarian Waterford Institute of Technology Ireland http://library.wit.ie/ T: ++353.51302838 M: ++353.876693212