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1Veertje - CC BY-SA 4.0
Jan Vilímek - Public Domain
unknown - Public Domain
Bruce Porteous - Public Domain
GFHund - CC BY 3.0
Edward Jenkins Harden - Public Domain
Transangst - CC BY-SA 3.0
see here for details: http://digitalgallery.nypl.org/nypldigital/id?1169097 - Public Domain
Genja Jonas - Public Domain
Ruben Ortega - CC BY-SA 4.0
Uuuxxxyyyzzz - CC BY-SA 4.0
United States Steel Corporation - Public Domain
Repro: Albert H. Payne († 1902) - Public Domain
caricata su en.wiki dall'ut. ScottyBoy900Q - Public Domain
KUNGL. BIBLIOTEKET - Public Domain
A. Kohl - Public Domain
Félix Nadar - Public Domain
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Norwid, Cyprian, 1821-1883
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1Veertje - CC BY-SA 4.0
Claerbout, David
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Heftel, Cecil, 1925-
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Jan Vilímek - Public Domain
Vrchlický, Jaroslav, 1853-1912
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unknown - Public Domain
Stribling, T. S. (Thomas Sigismund), 1881-1965
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Gual, Pedro, 1783-1862
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Bruce Porteous - Public Domain
Porteus, Beilby, 1731-1809
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Berlese, Antonio, 1863-1927
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Rawlinson, Henry Seymour Rawlinson, Baron, 1864-1925
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GFHund - CC BY 3.0
Peierls Rudolf E. (Rudolf Ernst), 1907-1995
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Edward Jenkins Harden - Public Domain
Troup, George Michael, 1780-1856
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Biya, Paul, 1933-....
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Transangst - CC BY-SA 3.0
Hughes, Shirley, 1927-....
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see here for details: http://digitalgallery.nypl.org/nypldigital/id?1169097 - Public Domain
Giuliani, Mauro, 1781-1829
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Juilliard, Augustus D.
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unknown - Public Domain
Maculani, Vincenzo
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Genja Jonas - Public Domain
Schwitters, Kurt, 1887-1948
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Gillette, Guy M. (Guy Mark), 1879-1973
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Seal (musician)
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Ruben Ortega - CC BY-SA 4.0
Colomo, Fernando, 1946-
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Uuuxxxyyyzzz - CC BY-SA 4.0
Nikodým, Otton Martin (1887-1974).
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unknown - Public Domain
Steffen, Hans, 1865-1936
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United States Steel Corporation - Public Domain
Aumont, Jean-Pierre
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Graun, Carl Heinrich, 1703?-1759
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Repro: Albert H. Payne († 1902) - Public Domain
Parepa-Rosa, Euphrosyne, 1836-1874
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caricata su en.wiki dall'ut. ScottyBoy900Q - Public Domain
Hopkins, Esek, 1718-1802
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KUNGL. BIBLIOTEKET - Public Domain
Nilsson, Sven, 1787-1883
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A. Kohl - Public Domain
Zeiller, Martin, 1589-1661
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Penniman, John Ritto, 1782 or 1783-1841
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Félix Nadar - Public Domain
Banville, Théodore Faullain de, 1823-1891