Chopra, J., & Sen, S. M. (2001). Unique quintessence of sociology for UPSC civil services preliminary examinations, P.C.S., S.S.C., universities and other competitive examinations (25th ed.). Unique Publishers.
Trích dẫn kiểu ChicagoChopra, J.K, và S. Mansukhani Sen. Unique Quintessence of Sociology for UPSC Civil Services Preliminary Examinations, P.C.S., S.S.C., Universities and Other Competitive Examinations. 25th ed. New Delhi: Unique Publishers, 2001.
Trích dẫn MLAChopra, J.K, và S. Mansukhani Sen. Unique Quintessence of Sociology for UPSC Civil Services Preliminary Examinations, P.C.S., S.S.C., Universities and Other Competitive Examinations. 25th ed. Unique Publishers, 2001.
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