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Photographer unknown. Subject (Hill) deceased. - Public Domain
Guy et Mockel (Pierre Mockel) - Public Domain
Maull & Polyblank - Public Domain
unknown - Public Domain
Randall & Pack, photographers - Public Domain
Louis Pescevic - CC BY-SA 4.0
Moshe Pridan - Public Domain
Boston9 - CC BY-SA 3.0
J. Rodgers - Public Domain
Georges Biard - CC BY-SA 3.0
Richard James Lane - Public Domain
Melsenbach - Public Domain
Michael Haas - CC BY-SA 3.0
John Faber Jean-Baptiste van Loo - Public Domain
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Photographer unknown. Subject (Hill) deceased. - Public Domain
Hill, A. V. (Archibald Vivian), 1886-1977
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Guy et Mockel (Pierre Mockel) - Public Domain
Redon, Odilon, 1840-1916
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Lahmann, H. (Heinrich), 1860-1905
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Edwards, Cliff, 1895-1971
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Maull & Polyblank - Public Domain
Bowerbank, J. S. (James Scott), 1797-1877
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unknown - Public Domain
Goclenius, Rudolph, 1572-1621
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Tucker, St. George, 1752-1827
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Randall & Pack, photographers - Public Domain
Bates, Henry M. (Henry Moore), 1869-1949
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Louis Pescevic - CC BY-SA 4.0
Miles, Jack, 1942-....
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Moshe Pridan - Public Domain
Woodcock, George, 1904-1979
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Leavitt, Henrietta Swan, 1868-1921
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Kirk, Edward Norris, 1802-1874
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Escherich, Theodor, 1857-1911
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Mallefille, Jean Pierre Félicien, 1813-1868
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unknown - Public Domain
Redfield, William Cox, 1858-1932
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Arria, Diego
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Woodhead, G. Sims (German Sims), 1855-1921
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Boston9 - CC BY-SA 3.0
Kropiwnicki, Jerzy, 1945-
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unknown - Public Domain
Wislicenus, Johannes, 1835-1902
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J. Rodgers - Public Domain
Talbot, Silas, 1751-1813
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Georges Biard - CC BY-SA 3.0
Bohringer, Romane
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Wilson, Ann, 1950-
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Stanley, Charles F.
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Richard James Lane - Public Domain
Anderson, James R. (James Robertson), 1811-1895
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Melsenbach - Public Domain
Ballantyne, R.M. (Robert Michael), 1825-1894
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Hudnut, William H., 1932-
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Elliott, George Augustus, 1717-1790
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Michael Haas - CC BY-SA 3.0
Haas, Michael, 1938-....
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unknown - Public Domain
Dell, Claudia, 1909-1977
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John Faber Jean-Baptiste van Loo - Public Domain
Heidegger, John James, 1659?-1748