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unknown - Public Domain
U.S. House of Representatives - Public Domain
Ernest Rude - CC BY-SA 4.0
NASA - Public Domain
Bain News Service, publisher - Public Domain
blahedo - CC BY-SA 2.5
Mathew Brady - Public Domain
Francisco Tristán - Public Domain
John Foster (illustrator), Increase Mather (author) - Public Domain
*:File:Naelachohanboutrosghali.jpg - Public Domain
Work of the US federal government and therefore in the public domain - Public Domain
original uploader - CC BY-SA 2.0
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Turney, Peter, 1827-1903
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unknown - Public Domain
Brett, Dorothy, 1883-1977
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Dix, W. Chatterton (William Chatterton), 1837-1898
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U.S. House of Representatives - Public Domain
Gutiérrez, Luis V. (Luis Vicente), 1953-
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Zhang, Xueliang, 1901-2001
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Ernest Rude - CC BY-SA 4.0
Mohr, Otto Lous
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NASA - Public Domain
Carpenter, M. Scott, 1925-2013
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Bain News Service, publisher - Public Domain
Rinehart, Mary Roberts, 1876-1958
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Shafer, Paul W. (Paul Werntz), 1893-1954
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Browning, Oscar, 1837-1923
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Belgrano, Manuel, 1770-1820
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Denis, Michael, 1729-1800
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unknown - Public Domain
Chauvenet, William, 1820-1870
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blahedo - CC BY-SA 2.5
Pickens, Andrew, 1739-1817
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Gray, Robert, 1762-1834
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Mathew Brady - Public Domain
Preston, William C. (William Campbell), 1794-1860
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Zarlino, Gioseffo, 1517-1590
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Zocchi, Giuseppe, 1711-1767
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Francisco Tristán - Public Domain
Medina, José Toribio, 1852-1930
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Fenn, Edward Hart, 1856-1939
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John Foster (illustrator), Increase Mather (author) - Public Domain
Mather, Richard, 1596-1669
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*:File:Naelachohanboutrosghali.jpg - Public Domain
Boutros-Ghali, Boutros, 1922-2016
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Work of the US federal government and therefore in the public domain - Public Domain
Jones, William Atkinson, 1849-1918
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Amici, Giovanni Battista, 1786-1863
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unknown - Public Domain
Wyman, Loraine
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Robinson, Jeanne
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Davids, T.W. Rhys (Thomas William Rhys), 1843-1922
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McKim, Charles Follen, 1847-1909
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original uploader - CC BY-SA 2.0
Smith, Lonnie, 1942-
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Agrippa von Nettesheim, Heinrich Cornelius, 1486?-1535