Other People's Family Planning: The Khanna Study . Population Problems in the Rural Punjab. John B. Wyon and John E. Gordon. Harvard University Press, Cambridge, Mass., 1971. xxvi, 438 pp., illus. $14.; The Myth of Population Control . Family, Caste, and Class in an Indian Village. Mahmood Mamdani. Monthly Review Press, New York, 1973. 174 pp. $7.95.