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unknown - Public Domain
Harris & Ewing, Inc. - Public Domain
Karel Kuklík - CC BY-SA 3.0
Author unknown - Public Domain
Selbymay - CC BY-SA 4.0
Unknown (pre-1923 photo) Watson, per the link in the source, left Johns Hopkins in 1921 (on bad terms). This is a photo of him there. - Public Domain
w - Public Domain
Chraa n - CC BY-SA 4.0
Photographer: White - Public Domain
Unknown photographer who worked for the CIA. - Public Domain
Anonymous - Public Domain
Eryia Amirian - CC BY 3.0
Photographer not named. - Public Domain
Fondazione Mansutti - Public Domain
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unknown - Public Domain
Standing, Herbert, 1846-1923
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Harris & Ewing, Inc. - Public Domain
Lomen, Carl J.
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Karel Kuklík - CC BY-SA 3.0
Boudník, Vladimír, 1924-1968
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Lopez, Sarah Rivera
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Otto I, Bishop of Freising, -1158
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Florence, William Jermyn, 1831-1891
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Author unknown - Public Domain
Hiller, Kurt, 1885-1972
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Heydt, Eduard von der, 1882-
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Selbymay - CC BY-SA 4.0
Frank
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Unknown (pre-1923 photo) Watson, per the link in the source, left Johns Hopkins in 1921 (on bad terms). This is a photo of him there. - Public Domain
Watson, John B. (John Broadus), 1878-1958
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w - Public Domain
Milhous, Katherine, 1894-1977
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Dundas, Hugh, 1920-
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Egerton, Wilbraham Egerton, Earl, 1832-1909
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Vann, Robert L., 1879-1940
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unknown - Public Domain
Brinkley, John, 1763-1835
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Brian, Donald
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Chraa n - CC BY-SA 4.0
Fatmi, Mounir, 1970-....
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Photographer: White - Public Domain
Lytton, L. Rogers, 1867-1924
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Romero de Terreros, Pedro, conde de Regla, 1710-1781
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unknown - Public Domain
Pansaers, Clément, 1885-1922
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Unknown photographer who worked for the CIA. - Public Domain
Hall, Virginia, 1906-1982
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Anonymous - Public Domain
Redmond, Granville, 1871-1935
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Eryia Amirian - CC BY 3.0
Mardikian, George M., 1903-
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Mason, James O., 1930-
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Wilson, Joseph Lapsley, 1844-1928
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Cohn, Alfred A., 1880-1951
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Dummer, Jeremiah, 1681-1739
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Photographer not named. - Public Domain
Hjort, Johan, 1869-1948
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McSween, Alexander A., 1844-1878
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Fondazione Mansutti - Public Domain
Molina, Luis de 1535-1600