Author
SpringerLink (Online service)
1,698
ScienceDirect (Online service)
1,132
Infobase,
529
Films for the Humanities & Sciences (Firm)
253
Infobase
253
Geological Survey (U.S.)
187
Geological Survey (U.S.),
111
Public Broadcasting Service (U.S.)
81
Oxford Scholarship Online
77
Jeon, Kwang W.
63
EBSCOhost
61
BBC (Firm)
53
Cerebellum Corporation
49
Cohn, Waldo E.
49
National Water-Quality Assessment Program (U.S.)
49
Moldave, Kivie, 1923-
48
BBC Worldwide Learning
42
Center for Biologics Evaluation and Research (U.S.)
37
United States. Environmental Protection Agency. Office of Water
34
Center for Drug Evaluation and Research (U.S.)
29
United States. Environmental Protection Agency
28
Off the Fence Productions
24
National Geographic Television & Film
23
Jeon, Kwang W.,
22
Russell, Frederick S. 1897-1984
21
BBC Worldwide Ltd
20
Library of Congress. Congressional Research Service,
20
United States. Environmental Protection Agency. Office of Research and Development
20
Bronner, Felix
19
American Public Television
18
Kleinzeller, Arnošt
18
National Geographic Society (U.S.)
18
RECOMB (Conference : 2005- )
18
United States. President (1993-2001 : Clinton)
18
Clinton, Bill, 1946-
17
Green Planet Films
17
Parthenon Entertainment (Firm)
17
Southward, Alan J.
17
Yonge, C. M. 1899-1986
17
CMSB (Conference)
16
Blaxter, J. H. S.
15
Discovery Education (Firm)
15
Ebooks Corporation
15
Film Ideas (Firm)
15
Inside Science (Firm)
15
Priami, Corrado
15
Schatten, Gerald
15
United States. Bureau of Land Management
15
Video Education Australasia
15
MVD (Firm)
14
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