ebrary, Inc 992
Films for the Humanities & Sciences (Firm) 876
Films Media Group 872
Adam Matthew Digital (Firm) 796
De Gruyter 755
National Science Foundation (U.S.) 670
SpringerLink (Online service) 647
Edgar Fahs Smith Memorial Collection (University of Pennsylvania) 569
Library of Congress Congressional Research Service 556
ProQuest (Firm) 462
William B. Provine Collection on Evolution and Genetics 443
National Academy of Sciences (U.S.) 412
Edward Potts Cheyney Memorial Fund 411
Royal Society (Great Britain) 396
WPA Film Library 388
Bacon, Francis, 1561-1626 380
National Center for Education Statistics 368
Descartes, René, 1596-1650 350
History of Science Collection (Brown University) 314
American Association for the Advancement of Science 311
Unesco 299
Educational Resources Information Center (U.S.) 277
Huxley, Thomas Henry, 1825-1895 259
Royal Society of Chemistry (Great Britain) 256
Boyle, Robert, 1627-1691 241
David E. Pingree Collection (Brown University) 227
O'Sullivan, Christine Y 224
Alexander Street Press 203
United States Congress 202
Humboldt, Alexander von, 1769-1859 192
Educational Testing Service 186
United States Congress. House. Committee on Science and Astronautics 185
National Science Teachers Association 167
United States Office of Educational Research and Improvement 164
Organisation for Economic Co-operation and Development 162
AM (Publisher) 161
Mark B. Adams Emergence of Modern Science Collection (University of Pennsylvania) 159
National Research Council (U.S.) 158
Académie des sciences (France) 153
National Assessment of Educational Progress (Project) 146
ProQuest ebook central 141
Tyndall, John, 1820-1893 141
Needham, Joseph, 1900-1995 140
Glasshead Productions 135
Aristotle 132
Smithsonian Institution 129
Brook Lapping Productions 125
Descartes, René, 1596-1650 125
History of Medicine Collection (David M. Rubenstein Rare Book & Manuscript Library) 125
Whitehead, Alfred North, 1861-1947 125
Akademii︠a︡ nauk SSSR 121
Helmholtz, Hermann von, 1821-1894 121
American Philosophical Society 115
Harvard University Graduate School of Education 115
Académie des sciences (France) 114
Gotham Book Mart Collection (University of Pennsylvania) 114
Sarton, George, 1884-1956 114
National Science Foundation (U.S.) Division of Science Resources Studies 110
Poincaré, Henri, 1854-1912 109
New York Academy of Sciences 108
Cambridge University Press 105
EBSCOhost 105
United States National Aeronautics and Space Administration 105
Mill, John Stuart, 1806-1873 103
United States Congress. House. Committee on Science and Astronautics. Subcommittee on Science, Research, and Development 102
Royal College of Physicians of London 100
Centre national de la recherche scientifique (France) 99
Institut istorii estestvoznanii︠a︡ i tekhniki (Akademii︠a︡ nauk SSSR) 98
James Hosmer Penniman Book Fund 98
Asimov, Isaac, 1920-1992 97
Cardano, Girolamo, 1501-1576 97
Kungl. Svenska vetenskapsakademien 96
Martinet, J. F (Joannes Florentius), 1729-1795 96
National Academy of Engineering 93
Alumni and Friends Memorial Book Fund 91
Culture Class Collection (University of Pennsylvania) 91
United States Congress. House. Committee on Foreign Affairs 91
Wolff, Christian, Freiherr von, 1679-1754 91
Rosengarten Family Fund 87
Unesco Science Cooperation Office for Latin America 87
American Society for Testing and Materials 85
ERIC Clearinghouse for Science, Mathematics, and Environmental Education 83
Institut filosofii (Akademii︠a︡ nauk SSSR) 83
Haldane, J. B. S (John Burdon Sanderson), 1892-1964 82
Institute of Medicine (U.S.) 81
National Institute of Education (U.S.) 81
Whewell, William, 1794-1866 81
United States Joint Publications Research Service 80
ASTM International 79
Popper, Karl R (Karl Raimund), 1902-1994 78
United States Congress. House. Committee on Science 78
Porta, Giambattista della, approximately 1535-1615 77
Russell, Bertrand, 1872-1970 77
Prelinger Archives (Firm) 76
Bronowski, Jacob, 1908-1974 75
Institute for Scientific Information 75
Martin, Benjamin, 1705-1782 75
British Association for the Advancement of Science 74
Taylor & Francis 74
United States 73