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Public Domain
Mathew Brady Levin Corot Handy - Public Domain
Scanned and digitized by Google Books, cropped by user Froggerlaura - Public Domain
unknown - Public Domain
Onehandclapping - CC BY-SA 3.0
Davis & Sanford - Public Domain
AppO - CC BY-SA 4.0
Andrew (bunnie) Huang - CC BY-SA 3.0
Wilhelm Höffert - Public Domain
John Ramspott - CC BY 2.0
Georges Biard - CC BY-SA 3.0
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Vane, John R.
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Genghis Khan, 1162-1227
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Public Domain
Baháʼuʼlláh, 1817-1892
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Mathew Brady Levin Corot Handy - Public Domain
Buckingham, William A. (William Alfred), 1804-1875
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Duisberg, Carl, 1861-1935
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Anne, Queen of Great Britain, 1665-1714
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Scanned and digitized by Google Books, cropped by user Froggerlaura - Public Domain
Abbe, Robert, 1851-1928
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Hough, Emerson, 1857-1923
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Appia, Adolphe, 1862-1928
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unknown - Public Domain
Catalani, Angelica, 1780-1849
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Piozzi, Hester Lynch, 1741-1821
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unknown - Public Domain
Glicenstein, Henryk, 1870-1942
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Onehandclapping - CC BY-SA 3.0
Kyger, Joanne
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Harvey, W. H. (William Hope), 1851-1936
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Davis & Sanford - Public Domain
Damrosch, Frank
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Jauner, Franz von 1832-1900
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Hotham, Charles, Sir, 1806-1855
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Tillmans, Wolfgang, 1968-....
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AppO - CC BY-SA 4.0
Mâche, François-Bernard
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Andrew (bunnie) Huang - CC BY-SA 3.0
O'Rear, Charles, 1941-
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Birkhoff, Garrett, 1911-1996
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Cotton, William Charles, 1813-1879
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unknown - Public Domain
Kölliker, Albert 1817-1905
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Wilhelm Höffert - Public Domain
Rubner, Max, 1854-1932
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Finch, Robert H., 1925-
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Medici, Carlo de' 1596-1666
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John Ramspott - CC BY 2.0
Taylor, Maggie, 1961-
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Georges Biard - CC BY-SA 3.0
Dern, Laura
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Ray, Ronald D.
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unknown - Public Domain
Ballivián, Adolfo, 1831-1873