Encyclopedia of psychotherapy; Volume 1
editors-in-chief, Michel Hersen, William Sledge
Academic Press, 2002
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The Encyclopedia Americana : volume 2
Grolier, 1994
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The Encyclopedia Americana : volume 2
Americana Corporation, 1977
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Encyclopedia of linguistics : volume 2
Philipp Strazny, editor
Fitzroy Dearborn, 2005
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Encyclopedia of knowledge : volume 2
Grolier Incorporated, 1991
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