Heer, D. M. (1992). Society and population. Prentice Hall.
Cita Chicago (17th ed.)Heer, David M. Society and Population. Englewood Cliffs, N. J.: Prentice Hall, 1992.
Cita MLA (9th ed.)Heer, David M. Society and Population. Prentice Hall, 1992.
Atenció: Aquestes cites poden no estar 100% correctes.