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Rob Bogaerts / Anefo - CC BY-SA 3.0
Edwin W. Morse - Public Domain
Eva Rinaldi - CC BY-SA 2.0
Kevin Tong, UC Davis College of Engineering - CC BY 2.0
unknown - Public Domain
Unknown or not provided - Public Domain
original uploader - Public Domain
No photographer credited. - Public Domain
United States Congress - Public Domain
Alexander Roslin - Public Domain
Nomo - CC BY 3.0
Robert Grau (1858-1916) - Public Domain
Men of Mark Publishing, Washington DC - Public Domain
Carl Gutherz - Public Domain
George Grantham Bain Collection (Library of Congress) - Public Domain
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Cabanilles, Juan
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Gaisford, Thomas, 1779-1855
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Rob Bogaerts / Anefo - CC BY-SA 3.0
Jong, Jacqueline de
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Edwin W. Morse - Public Domain
Mabie, Hamilton Wright, 1846-1916
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Eva Rinaldi - CC BY-SA 2.0
Napier, Jessica
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Gist, Mordecai, 1743-1792
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Hobson, J. Allan, 1933-....
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Leakey, Mary D. (Mary Douglas), 1913-1996
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Kevin Tong, UC Davis College of Engineering - CC BY 2.0
Vest, Charles M.
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Nalimov, V. V. (Vasiliĭ Vasilʹevich), 1910-1997
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Morland, George, 1763-1804
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unknown - Public Domain
Smyth, R. Brough (Robert Brough), 1830-1889
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Aleksandrov, A. V. (Aleksandr Vasilʹevich), 1883-1946
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Cameron, Donald Roderick, 1834-1905
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Unknown or not provided - Public Domain
Deng, Xiaoping, 1904-1997
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unknown - Public Domain
Lei, Zhen, 1897-1979
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Ritson, Joseph, 1752-1803
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Descartes, René, 1596-1650
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original uploader - Public Domain
Palmer, Potter
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No photographer credited. - Public Domain
Montgomery, Helen Barrett, 1861-1934
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United States Congress - Public Domain
Greene, Marjorie Taylor, 1974-
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Alexander Roslin - Public Domain
Holbach, Paul Henri Thiry, baron d', 1723-1789
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Nomo - CC BY 3.0
Phillips, Barre.
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Robert Grau (1858-1916) - Public Domain
Leonard, Marion, 1881-1956
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Men of Mark Publishing, Washington DC - Public Domain
Roberts, Ellis H. (Ellis Henry), 1827-1918
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Rojas, Cristóbal 1858-1890
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unknown - Public Domain
Rasmussen, Steen Eiler, 1898-1990
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Carl Gutherz - Public Domain
Marshall, William Rainey, 1825-1896
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Dmytryk, Edward
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George Grantham Bain Collection (Library of Congress) - Public Domain
Ashford, Daisy