Book 27,815 Government Document 7,899 Serial 1,800 Conference Proceeding 1,057 Electronic 946 Journal 545 Unknown 462 Book Chapter 194 Thesis 193 Map 58 Reference Material 44 Audio 26 Kit 13 Manuscript 12 Photo 12 Newspaper 2 Article 1 see all ...

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English 30,477 French 149 Chinese 146 German 118 Spanish 89 Russian 75 Japanese 55 Italian 34 Korean 16 Latin 14 Hungarian 10 Dutch 9 Portuguese 9 No linguistic content 7 Swedish 6 Thai 6 Czech 5 Hebrew 5 Turkish 4 Arabic 3 Finnish 3 Multiple 3 Polish 3 South American Indian 3 Austronesian 2 Central Khmer 2 Creole 2 Danish 2 Lithuanian 2 Undetermined 2 see all ...

Biography 3,634 Biographies 2,242 Electronic books 2,040 History 1,691 Periodicals 1,581 Congresses 1,421 Conference papers and proceedings 1,139 Statistics 809 Guidebooks 632 Directories 600 Identification 496 Autobiographies 450 Government publications 348 Field guides 344 Handbooks, manuals, etc 343 Bibliography 335 Pictorial works 320 Juvenile literature 265 Handbooks and manuals 258 Dictionaries 245 Observations 211 Congress 203 Classification 196 Maps 183 Catalogs 172 Juvenile works 169 Case studies 160 Documentary films 159 Bibliographies 147 Technical reports 141 see all ...

20th century 596 19th century 356 1900-1999 302 1785-1851 141 Cretaceous 129 1838-1914 120 1800-1899 118 1900 - 1999 118 1904-1967 103 From 65 to 140 million years ago 72 Tertiary 64 21st century 63 20e siècle 59 1907-1964 57 1918-1988 56 1955-2011 53 18th century 52 Pennsylvanian 51 1800 - 1899 50 Paleozoic 50 Permian 50 1879-1955 49 Jurassic 46 Quaternary 46 Mississippian 43 Devonian 41 Eocene 41 Mesozoic 39 1886-1948 37 1922- 37 see all ...