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AH Maurer - Public Domain
Jr155 - Public Domain
Albert Witzel - Public Domain
unknown - Public Domain
BPL - CC BY 2.0
Angel Rodriguez-Rey - CC BY-SA 2.0
Benson John Lossing - Public Domain
Cerchia di Tiziano - Cantalupo in Sabina (Rieti), Collezione Camuccini - Public Domain
Billinghurst -
Ministerio de Cultura de la Nación Argentina - CC BY-SA 2.0
e2a2j - Public Domain
Katarzyna Kozyra - CC BY-SA 3.0
Brady National Photographic Art Gallery. - Public Domain
unknown -
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Clapperton, Hugh, 1788-1827
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AH Maurer - Public Domain
Maurer, Alfred Henry, 1868-1932
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Malherbe, Charles, 1853-1911
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Spalding, A. G. (Albert Goodwill)
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Dupont, Alexis
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Gulick, John Thomas
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Jr155 - Public Domain
Soriano, Ferran, 1967-
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Albert Witzel - Public Domain
Bennett, Theron C., 1879-1937
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Donzelot, François-Xavier, 1764-1843
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unknown - Public Domain
Church, Benjamin, 1639-1718
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Dahl, Roald, 1916-1990
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Kunits, Luigi von, 1870-1931
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Powell, Mel
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Nichols, Kenneth D. (Kenneth David), 1907-
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BPL - CC BY 2.0
Purvis, Robert, 1810-1898
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Wańkowicz, Melchior, 1891-1974
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Angel Rodriguez-Rey - CC BY-SA 2.0
Iglesia, Álex de la, 1965-
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Benson John Lossing - Public Domain
Boyd, John Parker, 1764-1830
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Thacher, John Boyd, 1847-1909
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Cerchia di Tiziano - Cantalupo in Sabina (Rieti), Collezione Camuccini - Public Domain
Pius IV, Pope, 1499-1565
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Billinghurst -
Doyle, John Andrew, 1844-1907
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Oxenstierna, Axel, greve, 1583-1654
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Greenstein, Robert, 1946-
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Ministerio de Cultura de la Nación Argentina - CC BY-SA 2.0
Trouvé, Tatiana
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Kruger, Otto, 1885-1974
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e2a2j - Public Domain
Towers, John H. (John Henry), 1885-1955
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Katarzyna Kozyra - CC BY-SA 3.0
Kozyra, Katarzyna, 1963-....
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Brady National Photographic Art Gallery. - Public Domain
Harris, Benjamin G. (Benjamin Gwinn), 1806-1895
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Federico, da Montefeltro, Duke of Urbino, 1422-1482
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unknown -
Steklov, I︠U︡. M. (I︠U︡riĭ Mikhaĭlovich), 1873-1941