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- Lehmann, K. B. (Karl Bernhard), 1858-1940, author1
- Leonard, C. Henri (Charles Henri), 1850-19251
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- Leszynsky, W. M., author1
- Levy, Robert, 1864-19451
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- Library of the Surgeon-General's Office (U.S.)1
- Lilienthal, Howard, 1861-19461
- Lombroso, Cesare, 1835-19091
- Lowder, Wm. Lane (William Lane), author1
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- Magruder, E. M. (Edward May), 1858-1
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