Book 1,383,027 Conference Proceeding 127,874 Electronic 86,363 Government Document 49,267 Thesis 38,300 Journal 36,620 Serial 27,833 Book Chapter 12,025 Unknown 11,555 Map 2,149 Audio 718 Manuscript 662 Reference Material 522 Kit 454 Photo 359 Physical Object 59 Musical Score 29 Article 27 Newspaper 13 see all ...

SpringerLink (Online service) 47,238 ebrary, Inc 13,288 ProQuest (Firm) 12,366 Geological Survey (U.S.) 8,539 Institute of Electrical and Electronics Engineers 8,309 United States National Bureau of Standards 8,217 De Gruyter 5,201 IEEE Computer Society 4,768 Edgar Fahs Smith Memorial Collection (University of Pennsylvania) 4,508 Society of Photo-optical Instrumentation Engineers 4,471 IEEE Xplore (Online service) 4,108 William B. Provine Collection on Evolution and Genetics 3,625 History of Science Collection (Brown University) 3,377 National Institute of Standards and Technology (U.S.) 3,159 History of Medicine Collection (David M. Rubenstein Rare Book & Manuscript Library) 3,158 Association for Computing Machinery 2,384 National Science Foundation (U.S.) 2,352 World Scientific (Firm) 2,226 EBSCOhost 1,894 United States National Aeronautics and Space Administration 1,766 Smithsonian Institution 1,756 North Atlantic Treaty Organization Scientific Affairs Division 1,716 SPIE (Society) 1,682 Edward Potts Cheyney Memorial Fund 1,646 Alumni and Friends Memorial Book Fund 1,549 Cambridge University Press 1,531 ACM Digital Library 1,506 Darwin, Charles, 1809-1882 1,408 Wiley InterScience (Online service) 1,388 NetLibrary, Inc 1,381 see all ...

English 1,187,466 German 105,456 French 81,475 Russian 46,667 Spanish 23,644 Latin 19,082 Italian 17,326 Chinese 16,483 Japanese 9,293 Portuguese 5,953 Dutch 5,672 Polish 4,328 Arabic 3,536 Swedish 3,460 Korean 2,354 Danish 2,309 Undetermined 2,112 Czech 2,077 Indonesian 1,914 Hebrew 1,557 Multiple 1,496 Romanian 1,460 Ancient Greek 1,456 Hungarian 1,305 Vietnamese 1,093 Turkish 1,087 Ukrainian 1,034 Norwegian 1,003 Greek 901 Persian 822 see all ...

Congresses 159,976 Electronic books 127,604 Conference papers and proceedings 106,550 Periodicals 49,742 History 31,184 Biography 22,639 Early works to 1800 21,763 Technical reports 16,068 Congress 14,418 Biographies 14,046 Early works 14,022 Classification 12,934 Dictionaries 12,068 Guidebooks 11,238 Identification 11,087 Pictorial works 10,751 Academic theses 9,169 Juvenile literature 9,109 Handbooks, manuals, etc 9,018 Textbooks 8,539 Laboratory manuals 7,990 Bibliography 7,653 Periodical 7,538 Tables 7,057 Handbooks and manuals 6,826 Field guides 6,567 Congrès 6,465 Problems, exercises, etc 6,174 Popular works 5,647 Electronic journals 5,479 see all ...

Early works to 1800 5,957 20th century 4,482 19th century 4,116 Cretaceous 2,967 18th century 2,183 Quaternary 2,045 Tertiary 1,954 1809-1882 1,842 1900-1999 1,823 17th century 1,812 Devonian 1,679 Paleozoic 1,623 Pleistocene 1,595 1879-1955 1,517 Jurassic 1,347 1800-1899 1,330 Precambrian 1,250 From 65 to 140 million years ago 1,229 1564-1642 1,177 Carboniferous 1,164 Miocene 1,109 Ordovician 1,071 Cenozoic 1,067 Mesozoic 1,049 From 2 million years ago 1,030 Permian 1,030 Eocene 1,002 1642-1727 963 Silurian 956 Triassic 936 see all ...

United States 32,112 China 10,859 Germany 10,796 Great Britain 9,776 India 8,638 France 7,933 North America 7,879 Europe 6,365 Australia 6,309 California 6,174 Japan 6,019 England 5,844 Italy 5,576 Russia (Federation) 5,400 Soviet Union 4,956 Mexico 4,719 Canada 4,379 Brazil 3,833 Earth (Planet) 3,201 Alaska 3,165 New York (State) 3,152 Indonesia 2,911 Spain 2,890 Africa 2,794 Texas 2,556 South Africa 2,540 Sweden 2,521 Switzerland 2,431 Illinois 2,263 New Zealand 2,213 see all ...