Image from Wikimedia Commons
Eileen Darby, Graphic House - Public Domain
Santisolyluna - CC BY-SA 4.0
Knight Foundation - CC BY-SA 2.0
Brady & Co. (Washington, D.C.), photographer. - Public Domain
unknown - CC BY-SA 3.0
Michael Haas - CC BY-SA 3.0
unknown photographer -
National Photo Company Collection (Library of Congress) - Public Domain
Georges Seguin (Okki - CC BY-SA 3.0
unknown - Public Domain
original author and copyright not listed, digitized by Google Books (https://books.google.com/books?id=9ltNAAAAYAAJ&pg=PA470&dq=polo+%22j.m.+waterbury%22&hl=en&ei=h3GRTLs5gvjwBtPb6NsG&sa=X&oi=book_result&ct=result&resnum=2&ved=0CC4Q6AEwATge#v=onepage&q=polo%20%22j.m.%20waterbury%22&f=false) - Public Domain
unknown<br /> - Public Domain
ÑuÑuX - CC BY-SA 4.0
Taken by Katriel Cohn-Gordon - Public Domain
unidentified photographer - Public Domain
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Boynton, Henry V. (Henry Van), 1835-1905
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Dunstan, Donald
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Wilson, George, 1818-1859
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Eileen Darby, Graphic House - Public Domain
Hunter, Kim, 1922-2002.
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Skene, W. F. (William Forbes), 1809-1892
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Hall, Percival, 1872-1953
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Olin, Stephen, 1797-1851
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Mai, Mukhtar
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Sterling, Thomas, 1851-1930
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Blasco Ibáñez, Vicente, 1867-1928
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O'Conor, Roderic, 1860-1940
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Santisolyluna - CC BY-SA 4.0
Vostell, Wolf, 1932-1998
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Knight Foundation - CC BY-SA 2.0
Nasar, Sylvia.
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Brady & Co. (Washington, D.C.), photographer. - Public Domain
Harney, William S. (William Selby), 1800-1889
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Samaranch, Juan Antonio
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unknown - CC BY-SA 3.0
Gleditsch, Ellen, 1879-1968
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Michael Haas - CC BY-SA 3.0
Haas, Michael, 1938-....
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Pitcairn, William, 1711-1791
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unknown photographer -
Kirk, Norman Eric, 1923-1974
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Pomodoro, Giò, 1930-2002
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Gray, John Chipman, 1839-1915
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National Photo Company Collection (Library of Congress) - Public Domain
Williams, Margaret Lindsay, 1888-1960
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Georges Seguin (Okki - CC BY-SA 3.0
Urushihara, Satoshi, 1966-
Image from Wikimedia Commons
Quarles, Francis, 1592-1644
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unknown - Public Domain
Roberts, Isaac, Mrs., 1861-1942
Image from Wikimedia Commons
original author and copyright not listed, digitized by Google Books (https://books.google.com/books?id=9ltNAAAAYAAJ&pg=PA470&dq=polo+%22j.m.+waterbury%22&hl=en&ei=h3GRTLs5gvjwBtPb6NsG&sa=X&oi=book_result&ct=result&resnum=2&ved=0CC4Q6AEwATge#v=onepage&q=polo%20%22j.m.%20waterbury%22&f=false) - Public Domain
Berry, Martha, 1866-1942
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unknown<br /> - Public Domain
Merrick, Joseph Carey, 1862-1890
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ÑuÑuX - CC BY-SA 4.0
Portocarrero, René 1912-
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Taken by Katriel Cohn-Gordon - Public Domain
Gordon, Michael J.C., 1948-
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unidentified photographer - Public Domain
Varney, Louis, 1844-1908