TY - JOUR A1 - Price, Bronson T1 - Primary Biases in Twin Studies. A Review of Prenatal and Natal Difference-producing Factors in Monozygotic Pairs JF - The American Journal of Human Genetics, Vol. 2 (No. 4, Dec. 1950), pp. 293-352. Y1 - 1950 N1 - Xeroxcopy ER -