Book 1,316,490 Conference Proceeding 123,518 Electronic 60,026 Government Document 49,108 Thesis 38,136 Journal 35,210 Serial 27,266 Book Chapter 11,889 Unknown 10,404 Map 2,133 Manuscript 659 Audio 622 Reference Material 513 Kit 448 Photo 276 Physical Object 58 Musical Score 29 Article 26 Newspaper 19 see all ...

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English 1,120,223 German 103,849 French 79,733 Russian 46,065 Spanish 23,046 Latin 18,946 Italian 17,164 Chinese 16,101 Japanese 9,036 Portuguese 5,856 Dutch 5,608 Polish 4,210 Arabic 3,495 Swedish 3,425 Danish 2,286 Korean 2,236 Undetermined 2,075 Czech 2,022 Indonesian 1,876 Hebrew 1,507 Multiple 1,482 Ancient Greek 1,449 Romanian 1,439 Hungarian 1,299 Vietnamese 1,078 Turkish 1,067 Ukrainian 994 Norwegian 993 Greek 892 Persian 809 see all ...

Congresses 147,969 Electronic books 135,577 Conference papers and proceedings 106,111 Periodicals 47,955 History 30,842 Biography 22,181 Early works to 1800 21,597 Technical reports 16,054 Congress 14,401 Early works 13,871 Biographies 13,848 Classification 12,746 Dictionaries 11,955 Guidebooks 11,169 Identification 10,809 Pictorial works 10,539 Academic theses 9,096 Handbooks, manuals, etc 8,631 Textbooks 8,260 Juvenile literature 8,255 Laboratory manuals 7,955 Bibliography 7,611 Periodical 7,387 Electronic journals 7,343 Tables 6,997 Handbooks and manuals 6,778 Thèses et écrits académiques 6,720 Field guides 6,424 Congrès 6,418 Problems, exercises, etc 5,929 see all ...

Early works to 1800 5,954 20th century 4,290 19th century 3,965 Cretaceous 2,939 18th century 2,122 Quaternary 2,012 Tertiary 1,944 1900-1999 1,795 1809-1882 1,781 17th century 1,749 Devonian 1,671 Paleozoic 1,614 Pleistocene 1,584 1879-1955 1,454 Jurassic 1,333 1800-1899 1,310 Precambrian 1,244 From 65 to 140 million years ago 1,204 1564-1642 1,155 Carboniferous 1,146 Miocene 1,102 Ordovician 1,068 Cenozoic 1,057 Mesozoic 1,039 Permian 1,022 From 2 million years ago 1,014 Eocene 996 Silurian 945 1642-1727 939 Triassic 921 see all ...

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