Author
- Coal Run Improvement and Rail Road Company 2 results
- Nature Conservancy (U.S.) 2 results
- Pennsylvania 2 results
- Beauchamp, W. M. (William Martin), 1830-1925 1 results
- Blanchard, Newton Crain, 1849- 1 results
- Brazil 1 results
- Canada. Department of Agriculture 1 results
- Carey, Mathew, 1760-1839 1 results
- Conference on conservation of natural resources Washington) 1 results
- Cook, A. W. 1 results
- Dean, Heather 1 results
- Delaware Department of State Division of Historical and Cultural Affairs Historic Preservation Section 1 results
- Fox, Thomas G., 1936- 1 results
- Hummel, William W. 1 results
- Interstate Commission on the Delaware River Basin 1 results
- John Adams Library (Boston Public Library) 1 results
- McCarthy, G. Michael 1 results
- McGee, W J, 1853-1912 1 results
- North Dakota. Department of Agriculture and Labor 1 results
- Ontario. Department of Agriculture 1 results
- Pennsylvania A.W. Cook, Tract of Land Commission 1 results
- Pennsylvania State Planning Board 1 results
- Pennsylvania. Dept. of commerce 1 results
- Pennsylvania. Governor's Science Advisory Committee 1 results
- Pinchot, Gifford, 1865-1946 1 results
- Ridgway Oil, Coal, Lumber, and Mining Company 1 results
- Small, H. Beaumont (Henry Beaumont), 1832-1919 1 results
- Smithsonian Institution 1 results
- Steidle, Edward, 1887-1977 1 results
- United States. National Resources Planning Board 1 results
- Wyer, Samuel S., 1879-1955 1 results