SpringerLink (Online service) 2,035 Society of Photo-Optical Instrumentation Engineers 1,991 Geological Survey (U.S.) 1,734 North Atlantic Treaty Organization. Scientific Affairs Division 1,152 SPIE Digital Library 993 SPIE (Society) 716 International Business Machines Corporation. International Technical Support Organization 625 New York Academy of Sciences 614 Royal Society of Chemistry (Great Britain) 538 Cambridge University Press 502 American Mathematical Society 442 Safari, an O'Reilly Media Company 432 American Institute of Physics 429 National Science Foundation (U.S.) 369 Society for Industrial and Applied Mathematics 360 Smithsonian Institution 297 American Chemical Society. Meeting 288 International Conference on Human-Computer Interaction 281 LearningExpress (Organization) 263 Australia. Bureau of Mineral Resources, Geology and Geophysics 258 Geological Survey of Canada 253 American Geophysical Union 252 Darwin, Charles, 1809-1882 248 Ciba Foundation 246 Geological Society of London 243 MyJoVE Corporation 229 Jeon, Kwang W. 227 IEEE Computer Society 225 Early English Books Online Text Creation Partnership 218 Colorado Natural Heritage Program 206 World Meteorological Organization 205 International Astronomical Union. Symposium 200 Smithsonian Institution. Press 194 United States. National Aeronautics and Space Administration 183 Asimov, Isaac, 1920-1992 182 Centro internazionale matematico estivo 182 International Geological Congress 178 Jain, L. C. 178 University of Colorado at Denver. Center for Computational Mathematics 178 American Chemical Society 176 Colorado Geological Survey 165 International Astronomical Union 163 Geological Society of America 162 Società italiana di fisica 157 U.S. Fish and Wildlife Service 156 Pardalos, P. M. (Panos M.), 1954- 154 National Academy of Sciences (U.S.) 151 SAS Institute 151 British Geological Survey 150 Bourne, Geoffrey H. (Geoffrey Howard), 1909-1988 147 Centre national de la recherche scientifique (France) 144 LINK (Online service) 143 Moore, Patrick 143 ETAPS (Conference) 142 Katritzky, Alan R. 141 Chemical Society (Great Britain) 138 American National Standards Institute 135 Association for Computing Machinery 135 U.S. Atomic Energy Commission 135 Boyle, Robert, 1627-1691 132 Institute of Physics (Great Britain) 131 Danielli, J. F. (James Frederic), 1911-1984 128 Institute of Electrical and Electronics Engineers 127 Conference Board of the Mathematical Sciences 124 National Institute of Standards and Technology (U.S.) 124 World Scientific (Firm) 124 Stephanidis, Constantine 123 Unesco 123 National Audubon Society 122 National Council of Teachers of Mathematics 122 Consultants Bureau 121 Prigogine, I. (Ilya) 121 Geological Survey of Western Australia 119 Kacprzyk, Janusz 119 Abraham, Ajith, 1968- 118 Rice, Stuart Alan, 1932- 118 Bullfrog Films 117 International Federation for Information Processing 117 American Museum of Natural History 116 Nguyen, Ngoc Thanh (Computer scientist) 115 Organisation for Economic Co-operation and Development 114 American Astronomical Society 111 Optical Society of America 108 United Nations Environment Programme 108 Wolstenholme, G. E. W. (Gordon Ethelbert Ward) 108 National Research Council (U.S.) 107 Patai, Saul 107 Packer, Lester 103 Brewster, David, 1781-1868 100 European Physical Society 99 International Atomic Energy Agency 99 Krantz, Steven G. (Steven George), 1951- 99 North Dakota Geological Survey 99 Webb, G. A. (Graham Alan), 1935- 99 International School of Physics "Enrico Fermi" Varenna, Italy 98 McFedries, Paul 98 American Association for the Advancement of Science 97 International Union of Pure and Applied Chemistry 97 Mueller, John, 1958- 97 Hawkes, P. W. 96