Soil Survey of Harper County, Oklahoma [electronic resource] / United States Department of Agriculture, Natural Resources Conservation Service ; in cooperation with the Oklahoma Agricultural Experiment Station and the Oklahoma Conservation Commission.
Mode of access: Internet from the USDA web site. Address as of 6/11/2008: http://soildatamart.nrcs.usda.gov/Manuscripts/OK059/0/Harper.pdf; current access available via PURL.
Note
Title from title screen (viewed June 11, 2008).
"Issued 2006"--P. vii.
Bibliography
Includes bibliographical references (p. 615) and index to map sheets.