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unknown - Public Domain
U.S. Department of Education - Public Domain
Creencia05 - CC BY-SA 4.0
Karl Winkler (other date -
Public Domain
Mrkhlopov - CC BY-SA 4.0
Naval Research Laboratory -
author - Public Domain
Terryballard - CC BY-SA 3.0
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unknown - Public Domain
Clayton, William H. H. (William Henry Harrison), 1840-1920
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unknown - Public Domain
Ballivián, Adolfo, 1831-1873
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Willis, Nathaniel Parker, 1806-1867
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Béranger, Pierre-Jean de, 1780-1857
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U.S. Department of Education - Public Domain
Jennings, Kevin, 1963-
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Reid, George, 1841-1913
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Hardwicke, Philip Yorke, Earl of, 1757-1834
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unknown - Public Domain
Churchill, William, 1859-1920
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Frost, A.B. (Arthur Burdett), 1851-1928
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Creencia05 - CC BY-SA 4.0
Levay, Silvester
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Bel Geddes, Barbara
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Karl Winkler (other date -
Löhner, Fritz, 1883-1942
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Pendleton, Nat, 1895-1967
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Pelham, Thomas, Earl of Chichester, 1756-1826
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Public Domain
Turati, Filippo, 1857-1932
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Segall, Lasar, 1891-1957
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Mrkhlopov - CC BY-SA 4.0
Lawrence-King, Andrew
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Naval Research Laboratory -
Page, Robert Morris, 1903-1992
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Druschetzky, Georg, 1745-1819
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Denman, Thomas Denman, Baron, 1779-1854
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LaRouche, Lyndon H.,
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unknown - Public Domain
Parker, Isaac Charles, 1838-1896
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author - Public Domain
Buchanan, Robert Christie, 1811-1878
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Semmes, Raphael, 1809-1877
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Meissner, Sophie Radford de
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Daubenton, M. (Louis-Jean-Marie), 1716-1799
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Newman, William R., 1955-
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Terryballard - CC BY-SA 3.0
Grodin, Charles
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Public Domain
Gilmore, Mary, 1865-1962
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Leo I, Pope, -461