Title from title screen (viewed on Aug. 20, 2008).
"September 2002."
Includes bibliographical references.
Mode of access: Internet from the USGS web site. Address as of 8/20/08: http://pubs.usgs.gov/fs/2002/fs-090-02/pdf/fs-090-02%5Fver.1.1.pdf; current access available via PURL.