Wichman, Karl, author
Philadelphia, David McKay Company, 1944
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Mansion, J.E., author
London Harrap 1972-1980
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Wessely, J.E., author
Chicago dsb. Pollett Publ. 1946
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Klatt, Edmund
Berlin Langenscheidt KG. Verlag buchhandlung 1961
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Wichman, K., author
New York, David Mckay Company
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