http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Computer programs released as U.S. Geological Survey publications through August 1989
Title from title screen (viewed Apr. 24, 2009).
Includes bibliographical references and indexes.
This publication supersedes U.S. Geological Survey open-file report 86-172.
Electronic reproduction. [Reston, Va.] : U.S. Geological Survey, 1989. Mode of access: World Wide Web. System requirements: DJVU plug-in.
Mode of access: Internet from the USGS web site. Address as of 4/24/09: http://pubs.er.usgs.gov/djvu/OFR/1989/ofr%5F89%5F681.djvu ; current access available via PURL.
U.S. Geological Survey open-file report ; 89-681