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John Linnell - Public Domain
Seymour Lucas (painter) - Public Domain
Nachoom Assis - CC BY-SA 4.0
Bain News Service, publisher - Public Domain
Hubert von Herkomer - Public Domain
unknown - Public Domain
Mathew Brady Levin Corot Handy - Public Domain
Arthur - CC BY-SA 2.0
Unknown photographer - Public Domain
Rob Mieremet (ANEFO) - CC BY-SA 3.0
Australian News and Information Bureau -
Alexander Evgenievich Yakovlev - Public Domain
George Grantham Bain Collection (Library of Congress) - Public Domain
Ross-Stillman Productions, Inc. - Public Domain
Public Domain
David Shankbone - CC BY-SA 3.0
NIH historic image - Public Domain
the name of the photographer is unknown - Public Domain
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McInnes, W. B. (William Beckwith), 1889-1939
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Noble, Warren Perry, 1820-1903
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John Linnell - Public Domain
Malthus, T.R. (Thomas Robert), 1766-1834
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Coffin, Elizabeth R., 1850-1930
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Seymour Lucas (painter) - Public Domain
Ward, Rowland, 1848?-1912
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Nachoom Assis - CC BY-SA 4.0
Rozenblum, Yaʾir
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Bain News Service, publisher - Public Domain
Dallinger, Frederick W. (Frederick William), 1871-
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Hubert von Herkomer - Public Domain
Zimmern, Helen, 1846-1934
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Drouais, François Hubert (1727-1775).
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Haynes, Elwood, 1857-1925
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unknown - Public Domain
Throckmorton, Bess, 1565?-1647
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Mathew Brady Levin Corot Handy - Public Domain
Conover, Simon Barclay, 1840-1908
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Arthur - CC BY-SA 2.0
Pollack, Sydney, 1934-2008
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Mischakoff, Mischa, 1895-1981
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Unknown photographer - Public Domain
Trevor, John B. (John Bond), 1878-1956
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Rob Mieremet (ANEFO) - CC BY-SA 3.0
Tinbergen, Niko, 1907-1988
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Australian News and Information Bureau -
Banfield, E.J. (Edmund James), 1852-1923
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Alexander Evgenievich Yakovlev - Public Domain
Montenegro, Roberto, 1887-1968
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George Grantham Bain Collection (Library of Congress) - Public Domain
Frederik VIII, King of Denmark, 1843-1912
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Hoefnagel, Joris, 1542-1601
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Ross-Stillman Productions, Inc. - Public Domain
Jones, Henry, 1912-1999
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Public Domain
Duncan, Sara Jeannette, 1861-1922
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David Shankbone - CC BY-SA 3.0
Ricci, Christina
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unknown - Public Domain
Godman, Frederick Du Cane, 1834-1919
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NIH historic image - Public Domain
Gilman, Alfred Goodman, 1941-....
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Houdini, Harry, 1874-1926
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unknown - Public Domain
Orozco, Olga
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Corbin, Barry, 1940-
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the name of the photographer is unknown - Public Domain
Meredith, Adam
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March, Francis Andrew, 1825-1911