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Gerardus - Public Domain
Portrait by John Wollaston, Picture by Tayloe Cook - CC BY 3.0
Public Domain
Charles Roscoe Savage - Public Domain
Office of the Historian, U.S. House of Representatives - Public Domain
No photographer credited. - Public Domain
unknown - Public Domain
:en:Terry O. Morse - Public Domain
World Economic Forum - Remy Steinegger - CC BY-SA 2.0
Polkowski - Public Domain
Brady-Handy Photograph Collection (Library of Congress) - Public Domain
Boxes12 - CC BY-SA 3.0
Abraham de Vries - Public Domain
unknown photographer - Public Domain
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Prévost, Daniel
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Gerardus - Public Domain
Armitage, Kenneth, 1916-2002
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Basilius Valentinus
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Alamanni, Luigi, 1495-1556
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Portrait by John Wollaston, Picture by Tayloe Cook - CC BY 3.0
Tayloe, John, 1721-1779
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Goldsborough, Charles, 1765-1834
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Williams, Bransby, 1870-1961
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Public Domain
Austin, Warren Robinson, 1877-1962
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Topp, Erich
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Katz, Rudolf
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Carter, Stephen L., 1954-....
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Gaimard, Paul, 1790-1858
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Charles Roscoe Savage - Public Domain
Young, John W. (John Willard), 1844-1924
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Ferdinando I, Grand-Duke of Tuscany, 1549-1609
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Office of the Historian, U.S. House of Representatives - Public Domain
Remini, Robert V. (Robert Vincent), 1921-2013
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No photographer credited. - Public Domain
Fisher, Welthy Honsinger, 1879-1980
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unknown - Public Domain
Roussel, Ker-Xavier, 1867-1944
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Public Domain
Schwab, Michael, 1853-
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:en:Terry O. Morse - Public Domain
Herbert, Holmes E., 1882-1956
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World Economic Forum - Remy Steinegger - CC BY-SA 2.0
Harper, Stephen, 1959-....
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Borsuk, Karol
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unknown - Public Domain
Bonnand, Clément 1796-1861
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Polkowski - Public Domain
Kopczyński, Onufry, 1735-1817
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Champney, Elizabeth W. (Elizabeth Williams), 1850-1922
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Carter, Howard, 1874-1939
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Brady-Handy Photograph Collection (Library of Congress) - Public Domain
Hagans, John Marshall, 1838-1900
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Boxes12 - CC BY-SA 3.0
Tsvaygenbaum, Israel Iosifovich, 1961-
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Abraham de Vries - Public Domain
Vos, Simon de 1603-1676
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unknown photographer - Public Domain
Martin, William T., 1788-1866
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Vallisnieri, Antonio, 1661-1730