Description
Item Description:Title from PDF title screen (viewed on Feb. 13, 2007).
Electronic resource.
Physical Description:iii, 16 pages : digital, PDF file.
Format:Mode of access: Internet from the USGS web site. Address as of 10/5/07: http://md.water.usgs.gov/publications/ofr-2006-1335/ofr-2006-1335.pdf ; current access via PURL.
Bibliography:Includes bibliographical references (page 16).