United States Department of Agriculture, Natural Resources Conservation Service ; in cooperation with Maryland Agricultural Experiment Station (University of Maryland) ... [and others]
Includes bibliographical references (pages 179-180) and index to map sheets.
Mode of access: Internet from the USDA web site. Address as of 5/28/2008: http://soildatamart.nrcs.usda.gov/Manuscripts/MD027/0/MDHoward5%5F08.pdf; current access available via PURL.