Harbaugh, William Henry, author
Farrar, Straus and Cudahy, 1961
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Pringle, Henry Fowles, 1897-1958, author
Harcourt, Brace & World, 1956
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Cook, Fred J., author
Encyclopaedia Britannica Press, 1961
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Ludwig, Emil, 1881-1948, author
Garden City Publishing, 1941
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Dreiser, Theodore
A Premier Book, 1965
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