USMARC Format for bibliographic data (Cataloging Distribution Service, Library of Congress, 1994)
"A loose-leaf publication intended to be kept up-to-date by the periodic issuing of new and replacement pages. Supersedes the January 1988 edition and subsequent updates 1-4"–T.p. verso. Includes Update no. 1 (March 1995), Update no. 2 (March 1996), and Update no. 3 (July 1997).