Corey, Gerald
Theory and practice of group counseling
Brooks/Cole, Cengage Learning, 2012
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Group insurance
edited by William F. Bluhm, Daniel D. Skwire, Stephen J. Kaczmarek and Kristi M. Bohn
ACTEX Publications, 2012
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Kaplan, Harold I.
Comprehensive group psychotherapy
Williams & Wilklins , 1993
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Passman, Donald S.
The algebraic structure of group rings
John Wiley & Sons, 1979
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Joshi, A.W.
Elements of group theory for physicists
Wiley Eastern, 1982
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