Gopal, M. (1970). An Int to Research Procedure in Social sciences (2nd.). Asia Pub House.
Chicago-viite (17. p.)Gopal, M. An Int to Research Procedure in Social Sciences. 2nd. NULL: Asia Pub House, 1970.
MLA-viite (9. p.)Gopal, M. An Int to Research Procedure in Social Sciences. 2nd. Asia Pub House, 1970.
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