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Camilo José Vergara - CC BY-SA 3.0
Georges Biard - CC BY-SA 3.0
LZ6387 - CC BY-SA 4.0
Yorkeyorke14 - CC BY-SA 4.0
Public Domain
W. H. Maxwell - Public Domain
Heyward/Charlestown (circa 1865) - Public Domain
*:File:Otto_Struve_US_post_1949.JPG - Public Domain
author - Public Domain
Mathew Brady - Public Domain
unknown - Public Domain
US Congress - Public Domain
James Presley Ball (1825-1904) - Public Domain
Bieniecki Piotr - CC BY-SA 4.0
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Camilo José Vergara - CC BY-SA 3.0
Vergara, Camilo J.
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Georges Biard - CC BY-SA 3.0
Bouquet, Carole
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Sonthonax, Léger-Félicité, 1763-1813
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Isabella d'Este, consort of Francesco II Gonzaga, Marquis of Mantua, 1474-1539
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Matos-Rodríguez, Gerardo Hernán, 1898-1948
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LZ6387 - CC BY-SA 4.0
Young, Izzy, 1928-
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Foster, Rube, 1879-1930
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Yorkeyorke14 - CC BY-SA 4.0
Scelsi, Giacinto
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Public Domain
Burke, Edward R. (Edward Raymond), 1880-1968
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W. H. Maxwell - Public Domain
Maxwell, W. H. (William Hamilton), 1792-1850
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Heyward/Charlestown (circa 1865) - Public Domain
Chew, Roger Preston, 1843-1921
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*:File:Otto_Struve_US_post_1949.JPG - Public Domain
Struve, Otto, 1897-1963
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author - Public Domain
Jones, Samuel, 1819-1887
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Santorio, Santorio, 1561-1636
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Smith, Francis Hopkinson, 1838-1915
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Lyman, Lauren D. (Lauren Dwight), 1891-1971
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Elytēs, Odysseas, 1911-1996
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Jacobstein, Meyer, 1880-1963
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Mathew Brady - Public Domain
Wood, Fernando, 1812-1881
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Whitworth, Charles Whitworth, Earl, 1752-1825
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Leach, D. C. (DeWitt Clinton), 1822-1909
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Dalling and Bulwer, Henry Lytton Bulwer, Baron, 1801-1872
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unknown - Public Domain
Pick-Mangiagalli, Riccardo, 1882-1949
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US Congress - Public Domain
Denton, Jeremiah A.
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James Presley Ball (1825-1904) - Public Domain
Mantle, Lee, 1851-1934
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Bieniecki Piotr - CC BY-SA 4.0
Bitesnich, Andreas H., 1964-....
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Roby, John, 1793-1850
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unknown - Public Domain
Gates, Merrill Edwards, 1848-1922
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Jugurtha, King of Numidia, approximately 160 B.C.-104 B.C.
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Kurzweil, Allen.