The short answer to your question is "no," there's no way to query terms based on last modification date. However, and this feature needs publication on the website, there is an Atom feed that exposes the change activities for the subject headings: http://id.loc.gov/authorities/feed/ You can page through it (feed/page/1, feed/page/2). There is also a page that shows when each load was performed: http://id.loc.gov/authorities/loads/ It too has an Atom feed (http://id.loc.gov/authorities/loads/feed). HTH, Kevin >>> Ethan Gruber <[log in to unmask]> 05/13/10 3:14 PM >>> Does anyone know if it's possible to query terms at id.loc.gov by their last modification date? Here's an example of the current search results: http://id.loc.gov/authorities/search/?q=egypt The scenario is that I have a Solr service with all of the subject terms in it that I use for feeding autosuggest in an XForms application. My application comes packaged with the terms from an official rdf release from a few months ago. I'd like to improve my service by enabling a user to update their index with newly created or modified terms by the LOC after the date on which they ran the previous update. I could do this pretty easily if there was a way to query the authority list on id.loc.gov for terms modified after Feb. 15, 2010, for example. It seems there's no "advanced" search functionality as part of that interface, but maybe there's a sly way of passing additional query parameters. Thanks, Ethan