APA
Bell P. W., Todaro M. P. j. a., . (1969). Economic theory. New York: Oxford University Press.
Chicago
Bell Philip W, Todaro Michael P joint author, . 1969. Economic theory. New York: Oxford University Press.
Harvard
Bell P. W., Todaro M. P. j. a., . (1969). Economic theory. New York: Oxford University Press.
MLA
Bell Philip W, Todaro Michael P joint author, . Economic theory. New York: Oxford University Press. 1969.