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Jmabel -
original uploader - Public Domain
John Smart - Public Domain
Carlos Antunes - CC BY-SA 2.5
US Federal Government - Public Domain
unknown - Public Domain
National Photo Company Collection (Library of Congress) - Public Domain
not stated - Public Domain
FriendlyGhostUser - CC BY-SA 4.0
M. M. Mangasarian - Public Domain
Agriculus - CC BY 3.0
Βυθω - CC0 1.0
Artist unidentified - Public Domain
Alessandra Freguja - CC BY-SA 2.0
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Jmabel -
Cross, Charles R.
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Peterson, Collin C. (Collin Clark), 1944-
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Bach, Wilhelm Friedemann, 1710-1784
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Houk, L. C. (Leonidas Campbell), 1836-1891
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original uploader - Public Domain
Dubois, Eugène, 1858-1940
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John Smart - Public Domain
Clinton, Henry, Sir, 1738?-1795
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Carlos Antunes - CC BY-SA 2.5
Feira, Miguel Pereira Forjaz Coutinho Barreto de Sá e Resende, conde da, 1769-1827
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Boardman, Lee, 1972-
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US Federal Government - Public Domain
Schaufele, William E.
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Milva
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unknown - Public Domain
Boveri, Marcella
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National Photo Company Collection (Library of Congress) - Public Domain
Adams, Harriet Chalmers, 1875-1937
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not stated - Public Domain
Rittenhouse, Jessie B. (Jessie Belle), 1869-1948
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Campbell, William, Sir, 1758-1834
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Alexander, Geo. W. (George William), 1802-1890
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FriendlyGhostUser - CC BY-SA 4.0
Skousen, Royal.
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Brodrick, Cuthbert, 1821-1905
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Sibthorp, John, 1758-1796
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M. M. Mangasarian - Public Domain
Mangasarian, M. M. (Mangasar Mugurditch), 1859-1943
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Agriculus - CC BY 3.0
Fink, Siegfried
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Βυθω - CC0 1.0
Foyatier, Denis, 1793-1863
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Artist unidentified - Public Domain
Strong, Josiah, 1847-1916
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Suzuki, Takashi, 1949-....
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Willoughby, Francis, Sir, approximately 1547-1596
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Parkes, Samuel, 1759-1825
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Lamoureux, Lucien, 1888-1970
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Steffens, Lincoln, 1866-1936
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Ludwig, Christian Gottlieb, 1709-1773
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Alessandra Freguja - CC BY-SA 2.0
Rava, Enrico, 1939-....
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Alvaro, Corrado, 1895-1956