Author
ProQuest (Firm)
342 results
U.S. Fish and Wildlife Service
235 results
United States. Bureau of Biological Survey
145 results
Smithsonian Institution
91 results
Peterson, Roger Tory, 1908-1996
60 results
Texas. Parks and Wildlife Department
52 results
Audubon, John James, 1785-1851
44 results
United States. Congress. House. Committee on Agriculture
41 results
American Ornithologists' Union
40 results
National Audubon Society
37 results
Smithsonian Institution. Office of the Secretary
34 results
United States. Forest Service
31 results
United States. Department of Agriculture
29 results
United States. Congress. House. Committee on Merchant Marine and Fisheries
28 results
United States. Congress. Senate. Committee on Environment and Public Works
28 results
Bewick, Thomas, 1753-1828
27 results
Hudson, W. H. (William Henry), 1841-1922
26 results
Rand, Austin Loomer, 1905-1982
24 results
Association of Avian Veterinarians
23 results
SpringerLink (Online service)
23 results
United States. Congress. House
23 results
Geological Survey (U.S.)
22 results
Library of Congress. Congressional Research Service
22 results
NetLibrary, Inc
22 results
Skutch, Alexander F. (Alexander Frank), 1904-2004
22 results
United States National Museum
22 results
Wetmore, Alexander, 1886-1978
22 results
Bent, Arthur Cleveland, 1866-1954
21 results
Johnsgard, Paul A.
21 results
United States. Congress. Senate. Committee on Agriculture and Forestry
21 results
Gale (Firm)
20 results
United States. Department of Agriculture. Office of the Secretary
20 results
Geological and Geographical Survey of the Territories (U.S.)
19 results
Grinnell, Joseph, 1877-1939
19 results
Sutton, George Miksch, 1898-1982
19 results
Coues, Elliott, 1842-1899
18 results
Gould, John, 1804-1881
17 results
United States. Bureau of Land Management
17 results
United States. National Park Service
17 results
ebrary, Inc
17 results
Traylor, Melvin A. (Melvin Alvah), 1915-2008
16 results
Academy of Natural Sciences of Philadelphia
15 results
Association of Avian Veterinarians. Conference & Expo
15 results
Bergman, Eric
15 results
Chapman, Frank M. (Frank Michler), 1864-1945
15 results
National Geographic Society (U.S.)
15 results
Rocky Mountain Forest and Range Experiment Station (Fort Collins, Colo.)
15 results
American Association of Avian Pathologists
14 results
Blake, Emmet Reid, 1908-1997
14 results
Dorset, Catherine Ann Turner, 1750?-1817?
14 results
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