Periodicals>Journal Article:  Dobzhansky , Theodosius and Allen, Gordon (1956), Does Natural Selection Continue to Operate in Modern Mankind?', American Anthropologist, 1956, 58, 595, Retrieved on 2012-04-25

Books, Brochures, and Chapters>Book:  Dobzhansky , Theodosius Grigorievich and Dobzhansky , Theodosius (1937), Genetics and the origin of species, Columbia Univ Pr, Retrieved on 2012-04-25

Source Material [books.google.com]