SCHAEFER, R. T. (1989). Sociology Richard T. Schaefer; In Collabration With Robert P. Lamn. McGraw-Hill.
Chicago-viite (17. p.)SCHAEFER, Richard T. Sociology Richard T. Schaefer; In Collabration With Robert P. Lamn. McGraw-Hill, 1989.
MLA-viite (8. p.)SCHAEFER, Richard T. Sociology Richard T. Schaefer; In Collabration With Robert P. Lamn. McGraw-Hill, 1989.
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