Author
Geological Survey (U.S.)
63
United States. Administration on Aging
17
United States. Congress. Senate. Committee on Energy and Natural Resources
17
Educational Resources Information Center (U.S.)
14
United States. Bureau of Mines
14
United States. Congress. House. Committee on Resources
13
United States. Congress. Senate. Committee on Appropriations. Subcommittee on Departments of Labor, Health and Human Services, Education, and Related Agencies
8
Chester County Water Resources Authority
7
Conger, Randall W.
7
Northeastern Forest Experiment Station (Radnor, Pa.)
7
Pennsylvania. Bureau of Topographic and Geologic Survey
6
United States. Environmental Protection Agency
6
Pennsylvania. Bureau of Mining and Reclamation
5
Air and Energy Engineering Research Laboratory
4
Lincoln University (Pa.)
4
Ramashala, Mapule F.
4
Schreffler, Curtis L.
4
United States. Congress. House. Committee on Interior and Insular Affairs
4
United States. Congress. House. Committee on Natural Resources
4
United States. Congress. House. Committee on Public Works and Transportation. Subcommittee on Public Buildings and Grounds
4
United States. Congress. House. Committee on Transportation and Infrastructure
4
United States. Congress. Senate. Committee on the Judiciary
4
United States. Department of Education
4
United States. National Park Service
4
Wood, Charles R.
4
America's Industrial Heritage Project
3
Central Susquehanna Intermediate Unit
3
Drake, Avery Ala, 1927-
3
Forest Products Laboratory (U.S.)
3
Goode, Daniel J.
3
Kostelnik, Kevin M.
3
New Hope (Pa.)
3
Robertson, Andrew, 1936-
3
Sames, Gary P.
3
Scott, A. G.
3
Sloto, Ronald A.
3
Stanton, Ronald W.
3
United States. Army. Corps of Engineers
3
United States. Congress. House. Committee on Education and Labor. Subcommittee on Labor-Management Relations
3
United States. Congress. House. Committee on Public Works and Transportation
3
United States. Congress. House. Committee on Resources. Subcommittee on National Parks, Recreation, and Public Lands
3
United States. Congress. House. Committee on Veterans' Affairs. Subcommittee on Oversight and Investigations
3
United States. Forest Service
3
United States. Navy Department
3
United States. Office of Surface Mining Reclamation and Enforcement
3
Witt, Emitt C.
3
Allegheny National Forest (Agency : U.S.)
2
Bauer, Eric R.
2
Bilger, Michael D.
2
Bird, Philip H.
2
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