Book 81,893 Government Document 26,586 Serial 11,008 Journal 5,240 Electronic 4,548 Conference Proceeding 4,056 Thesis 1,247 Unknown 924 Kit 816 Reference Material 293 Audio 285 Manuscript 127 Map 100 Photo 42 Book Chapter 34 Article 12 Musical Score 1 Newspaper 1 Physical Object 1 see all ...

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20th century 2,068 1900-1999 916 21st century 618 19th century 508 1900 - 1999 261 2000-2099 223 1945- 208 20e siècle 192 1800-1899 150 18th century 139 1939-1945 130 1800-1999 98 Since 1945 93 1991- 86 17th century 69 21e siècle 67 20e siècle 62 1989- 54 1900-2099 52 1933-1945 51 19e siècle 51 To 1500 50 1700-1799 48 Since 1991 48 1945-1989 47 1947- 46 1942- 45 Geschichte 45 1935- 42 1936- 39 see all ...