It is possible to search HLAS records from the 1970s 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: lx2.loc.gov
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/
To do this, in EndNote, search for the connection files: https://endnote.com/downloads/connection-files/. Enter Library of Congress in the search box. You will see the HLAS connection file is listed under Library of Congress. Or you can download the file directly: https://endnote.com/connections_download/library-of-congress-2/ (click Download Connection).