1 folded sheet (6 pages) : color illustrations ; 28 cm
OCLC
ocm51307568, ocm50427648
Caption title.
Shipping list no.: 2002-0281-P.
"July 2002"--P. [6].
Includes bibliographical references (page [6]).
Also available via Internet from the USGS web site. Address as of 9/16/02: http://water.usgs.gov/pubs/FS/fs05302/pdfs/rbfs053.pdf ; current access is available via PURL.