Zimmerman, L. J. (1965). Poor lands, rich lands: The widening gap. Random House.
Chicago Style aipamenaZimmerman, Louis Jacques. Poor Lands, Rich Lands: The Widening Gap. New York: Random House, 1965.
MLA aipamenaZimmerman, Louis Jacques. Poor Lands, Rich Lands: The Widening Gap. Random House, 1965.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.