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Harris & Ewing - Public Domain
National Institutes of Health (NIH) - Public Domain
Emilius Bærentzen and C. M. Tegner; - Public Domain
Andy Miah - CC BY-SA 2.0
unknown - Public Domain
Herbert E. Abrams, under commission of the United States Court of Appeals for the District of Columbia Circuit - Public Domain
US Government - Public Domain
Post of Ecuador - Public Domain
Librairie Générale Scientifique et Industrielle, H. Desforges - Public Domain
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Wilson, James Grant, 1832-1914
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Harris & Ewing - Public Domain
Berger, Victor L. (Victor Luitpold), 1860-1929
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National Institutes of Health (NIH) - Public Domain
Schulman, Sarah, 1958-....
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Karnes, Henry Wax, 1812-1840
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Mulier, Pieter, 1637-1701
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Molière, 1622-1673
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Vaile, William Newell, 1876-1927
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Fife, William, 1858-1944
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Klügel, Georg Simon, 1739-1812
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Emilius Bærentzen and C. M. Tegner; - Public Domain
Nielsen, Augusta, 1822-1902
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Ballenger, Cass, 1926-
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Benezet, Anthony, 1713-1784
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Andy Miah - CC BY-SA 2.0
Sinclair, Iain, 1943-....
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Mackenzie, Henry, 1745-1831
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Faucher, Léon, 1803-1854
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Kramers, Hendrik Anthony, 1894-1952
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unknown - Public Domain
Kuykendall, Dan
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Winchester, James, 1752-1826
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Pegge, Samuel, 1704-1796
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Herbert E. Abrams, under commission of the United States Court of Appeals for the District of Columbia Circuit - Public Domain
Wilkey, Malcolm Richard
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Holland, Matthew Scott, 1966-
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Castilla, Ramón, 1797-1867
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Hillhouse, James, 1754-1832
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Gabriel, Ruth, 1976-
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Gompers, Samuel, 1850-1924
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US Government - Public Domain
Lloyd, Lola Maverick, 1875-1944
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Dejerine, J. (Jules), 1849-1917
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Post of Ecuador - Public Domain
Aguilera-Malta, Demetrio, 1909-1981
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Librairie Générale Scientifique et Industrielle, H. Desforges - Public Domain
Rühmkorff, Heinrich Daniel 1803-1877
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Humphreys, Benjamin G. (Benjamin Grubb), 1865-1923