Cita APA (7th ed.)
Wrigley, E. A. (1974). Population and history. McGraw-Hill.
Cita Chicago (17th ed.)
Wrigley, E. A. Population and History. New York ; Toronto: McGraw-Hill, 1974.
Cita MLA (9th ed.)
Wrigley, E. A. Population and History. McGraw-Hill, 1974.
Atenció: Aquestes cites poden no estar 100% correctes.