Author
Barker, James L., 1936-
Geological Survey (U.S.)
8 results
United States. Army. Corps of Engineers. Philadelphia District
5 results
Hainly, Robert A.
2 results
United States. Environmental Protection Agency
2 results
Witt, Emitt C.
2 results
Geological Survey (U.S.). Water Resources Division
1 results
Kulp, Kenneth P.
1 results
United States. Soil Conservation Service
1 results