Corey, G. (1990). Theory and practice of group counselling (3rd ed.). Brooks/Cole Publishing.
Dyfyniad Arddull ChicagoCorey, Gerald. Theory and Practice of Group Counselling. 3rd ed. California.: Brooks/Cole Publishing, 1990.
Dyfyniad MLACorey, Gerald. Theory and Practice of Group Counselling. 3rd ed. Brooks/Cole Publishing, 1990.
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