It is now possible to search HLAS records (Vols. 50-onward) using a Z39.50 client or bibliographic citation tools such as Zotero, EndNote (see below), or Refworks.
Internet Addresses, Databases, Hours of Availability
Domain Name: z3950.loc.gov (188.8.131.52)
For complete technical information for z39.50 connection and access, please see the LC Z39.50 Server Configuration Guidelines: http://www.loc.gov/z3950/lcserver.html
It is also possible to access the HLAS database by using the appropriate search forms listed under “Search HLAS catalog” on the LC Gateway page: http://www.loc.gov/z3950/gateway.html
To do this, in EndNote 6-X go to the Tools menu and choose Connect; slide over the Connect command to get the window entitled Choose A Connection File. (Note: Versions of EndNote prior to 6 have the Connect command available from the File menu.) The Find button on the left-hand side about two-thirds of the way down the window will narrow your options. NOTE: HLAS is listed under Library of Congress.
Alternatively, here is the link to the HLAS connection file: http://endnote.com/downloads/connections/library-congress-0