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V. Floyd Campbell - Public Domain
Alexander Roslin - Public Domain
Herbert Rose Barraud (1845-1896) - Public Domain
KTo288 - CC BY-SA 3.0
Juan Amills-Biblioteca Nacional de España - CC BY-SA 4.0
United States Federal Government - Public Domain
George Engleheart - Public Domain
Hanna Toresson - CC BY-SA 3.0
SP - Public Domain
:sv:Per Bagge (1866-1936) - Public Domain
Upton Sinclair - Public Domain
unknown - CC BY-SA 3.0
unknown photographer - Public Domain
unknown - Public Domain
''':de:Ludwig Schwab (Fotograf) -
Xavier Martinez - Public Domain
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Brady, Hugh, 1768-1851
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Addonizio, Hugh J., 1914-1981
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Palafox y Mendoza, Juan de 1600-1659
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Starke, Pauline, 1901-1977
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V. Floyd Campbell - Public Domain
Doubleday, Frank Nelson, 1862-1934
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Foster, Pops, 1892-1969
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Alexander Roslin - Public Domain
Holbach, Paul Henri Thiry, baron d', 1723-1789
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Herbert Rose Barraud (1845-1896) - Public Domain
Brough, Fanny Whiteside, 1854-1914
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KTo288 - CC BY-SA 3.0
Walters, Ian
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Juan Amills-Biblioteca Nacional de España - CC BY-SA 4.0
González, Diego Tadeo, 1731 or 1732-1794
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United States Federal Government - Public Domain
Clark, William Bullock, 1860-1917
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George Engleheart - Public Domain
Thompson, Thomas Boulden, 1766-1828
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Tetrazzini, Luisa
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Walser, Martin, 1927-....
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Hanna Toresson - CC BY-SA 3.0
Gruen, Bob
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SP - Public Domain
Royer, Pancrace, 1705?-1755
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:sv:Per Bagge (1866-1936) - Public Domain
Rydberg, J. R. (Johannes Robert), 1854-1919
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Williams-Wynn, Watkin, 1749-1789
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Wells, Samuel, 1965-
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Rabaut, Louis C. (Louis Charles), 1886-1961
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Guernsey, Frank Edward, 1866-1927
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Churchill, Marguerite, 1910-2000
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Upton Sinclair - Public Domain
Sinclair, Mary Craig
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Temple, Mary B. (Mary Boyce), 1856-
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Kauffmann, Angélica 1741-1807
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unknown - CC BY-SA 3.0
Fichet, Guillaume, 1433-approximately 1480
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unknown photographer - Public Domain
Johnson, Osa, 1894-1953
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unknown - Public Domain
Hartmann, Moritz, 1821-1872
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''':de:Ludwig Schwab (Fotograf) -
Strnad, Oskar, 1879-1935
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Xavier Martinez - Public Domain
Martinez, Xavier, 1869-1943