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Willem van de Poll - CC BY-SA 3.0
Sammlung Varnhagen - Public Domain
Hreinn Gudlaugsson - CC BY-SA 4.0
Dr. Susan Hardwicke - CC BY-SA 3.0
original uploader - Public Domain
Hanns Holdt - Public Domain
:w:en:Mathew Brady (1822-1896) or :w:en:Levin Corbin Handy (1855–1932) - Public Domain
Mathew Brady Levin Corot Handy - Public Domain
Office of the Attorney General of California -
Ron Kroon / Anefo - CC BY-SA 3.0
unknown photographer circa 1915 - Public Domain
artwork drawn by Adolph Boÿ, engraved by Jeremias Falck - Public Domain
Martin Bernigeroth - Public Domain
unknown - Public Domain
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Ogier, Bulle, 1939-....
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Fergusson, James, 1832-1907
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Jacobi, Viktor, 1883-1921
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Taylor, James Hudson, 1832-1905
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Willem van de Poll - CC BY-SA 3.0
Helfrich, Conrad E. L. (Conrad Emile Lambert), 1886-1962
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Johannes, Metropolitan of Helsinki, 1923-
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Sammlung Varnhagen - Public Domain
Robert, Ludwig, 1778-1832
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McKennan, Thomas McKean Thompson, 1794-1852
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Hreinn Gudlaugsson - CC BY-SA 4.0
Robertson, Sherman
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Dr. Susan Hardwicke - CC BY-SA 3.0
DioGuardi, Joseph J., 1940-
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original uploader - Public Domain
Matteucci, Carlo, 1811-1868
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Mann, Heinrich, 1871-1950
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Wilder, Marshall P. (Marshall Pinckney), 1859-1915
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Hanns Holdt - Public Domain
Sandberger, Adolf, 1864-1943
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Proudhon, P.-J. (Pierre-Joseph), 1809-1865
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Ingrao, Pietro.
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:w:en:Mathew Brady (1822-1896) or :w:en:Levin Corbin Handy (1855–1932) - Public Domain
Marsh, Othniel Charles, 1831-1899
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Valle-Inclán, Ramón del, 1866-1936
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Arledge, John, 1907-1947
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Isabella I, Queen of Spain, 1451-1504
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Mathew Brady Levin Corot Handy - Public Domain
Hubbell, Jay A. (Jay Abel), 1829-1900
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Graham, Martha, 1894-1991
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Wilson, Lois, 1895-1988
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Office of the Attorney General of California -
Lynch, Thomas C. (Thomas Connor), 1904-1986
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Ron Kroon / Anefo - CC BY-SA 3.0
Neild, R. R.
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unknown photographer circa 1915 - Public Domain
Veblen, Oswald, 1880-1960
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artwork drawn by Adolph Boÿ, engraved by Jeremias Falck - Public Domain
Alhazen, 965-1039
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Browne, Edward Granville, 1862-1926
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Martin Bernigeroth - Public Domain
Werenfels, Samuel, 1657-1740
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unknown - Public Domain
Douglas, Charlie, 1840-1916