Levinson, David, author
New York: G.K. Hall & Company; 1996,
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GK-Hall, 1994
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Hastings, James, author
T&T Clark, 1980
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edited by C.A. Jacobson and Clifford A. Hampel
Van Nostrand Reinhold, 1959
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Pandey, A.K., author
Anmol Publications, 1992
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