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Gage Skidmore - CC BY-SA 3.0
Bowman - Public Domain
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unknown - Public Domain
John C. H. Grabill - Public Domain
Muesse - CC BY 3.0
Bertall - Public Domain
Nathalie SZWIEC - CC BY-SA 3.0
Francisco de Comontes - Public Domain
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XIII - CC BY-SA 3.0
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*:File:Otto_Struve_US_post_1949.JPG - Public Domain
Charles Augustus Mornewick - Public Domain
Claude Joannis - CC BY-SA 2.0
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Williams, J.Whitridge (John Whitridge), 1866-1931
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Saulcy, Félicien de, 1807-1880
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Lugo, Juan de 1583-1660
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Gage Skidmore - CC BY-SA 3.0
Williams, Billy Dee, 1937-....
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Bowman - Public Domain
Todd, Dick
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Gale, Thomas, 1507-1587
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Ponsonby, Henry Frederick, Sir, 1825-1895
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US government - Public Domain
Fowler, Henry H., 1908-2000
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unknown - Public Domain
Reed, John Oren, 1856-1916
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Lee, Russell, 1903-1986
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John C. H. Grabill - Public Domain
Watson, Elmo Scott, 1892-1951
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Howard, Oliver Otis, 1830-1909
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Bakunin, Mikhail Aleksandrovich, 1814-1876
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Muesse - CC BY 3.0
Spranger, Eduard, 1882-1963
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Bertall - Public Domain
Sainte-Beuve, Charles-Augustin, 1804-1869
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Nathalie SZWIEC - CC BY-SA 3.0
Padilla, Jose
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Walsh, Thomas James, 1859-1933
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Anglesey, Arthur Annesley, Earl of, 1614-1686
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Bateson, Mary Catherine
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Francisco de Comontes - Public Domain
Martínez Síliceo, Juan, 1486-1557
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Sailko - CC BY-SA 3.0
Platina, 1421-1481
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CBS Television - Public Domain
Perkins, Carl, 1932-1998
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XIII - CC BY-SA 3.0
Du Perron, Jacques Davy, 1556-1618
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original uploader - Public Domain
Lucas, Jack, 1928-2008
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Green, Richard R., 1936-1989
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Brailowsky, Alexander, 1896-1976
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Ferry, Jules, 1832-1893
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*:File:Otto_Struve_US_post_1949.JPG - Public Domain
Struve, Otto, 1897-1963
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Charles Augustus Mornewick - Public Domain
Llanover, Augusta Hall, 1802-1896
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Claude Joannis - CC BY-SA 2.0
Marchand, Erik