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Trevor H. Hall - Public Domain
unknown - Public Domain
Yustas - CC BY-SA 3.0
CarlosManzanoPHOTOs - CC BY-SA 3.0
Desconocido (principios s. XIX) - Public Domain
Goodwin & Company - Public Domain
Guttiwuts - CC BY-SA 3.0
Friedrich Brandseph - Public Domain
redfalo - CC BY-SA 2.0
Order of Railroad Telegraphers - Public Domain
*:File:Henry_Kendall_by_Tom_Frost.jpg - CC BY-SA 3.0
Public Domain
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Pugh, Jim
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Trevor H. Hall - Public Domain
Hall, Trevor H.
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Cowie, William Garden, 1831-1902
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Giacomelli, Geminiano, approximately 1692-1740
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Brown, William G. (William Gay), 1800-1884
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Vallotton, Félix, 1865-1925
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unknown - Public Domain
Baldwin, Oliver, 1899-1958
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Reynier, J.L.E.
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Boucherett, Emilia J.
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unknown - Public Domain
Brockdorff-Rantzau, Ulrich, Graf, 1869-1928
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Bates, William, 1625-1699
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Yustas - CC BY-SA 3.0
Vishnevskaya, Galina
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unknown - Public Domain
Semenov, N. N. (Nikolaĭ Nikolaevich), 1896-1986
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CarlosManzanoPHOTOs - CC BY-SA 3.0
Edwards, Mickey, 1937-
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Desconocido (principios s. XIX) - Public Domain
Guise, Martín Jorge, 1780-1828
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Goodwin & Company - Public Domain
Morrill, John F., 1855-1932
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Guttiwuts - CC BY-SA 3.0
Wallace, Barbara Brooks, 1922-
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unknown - Public Domain
Todd, Paul Harold, 1921-2008
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Edlund, Erik, 1819-1888
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Ayres, William Augustus, 1867-1952
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Barondess, Joseph, 1867-1928
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Johnston, George, 1797-1855
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Price, E. Hoffmann
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Allen, John M. (John Mills), 1846-1917
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Friedrich Brandseph - Public Domain
Pfau, Ludwig, 1821-1894
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redfalo - CC BY-SA 2.0
Granger, C. W. J. (Clive William John), 1934-2009
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Bowditch, Henry I. (Henry Ingersoll), 1808-1892
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Order of Railroad Telegraphers - Public Domain
Ryan, William H. (William Henry), 1860-1939
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*:File:Henry_Kendall_by_Tom_Frost.jpg - CC BY-SA 3.0
Kendall, Henry W. (Henry Way), 1926-1999
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Public Domain
Locher, Cyrus, 1878-1929