Heer, D. M. (1975). Society and population (2nd ed.). Prentice-Hall.
Cita Chicago (17th ed.)Heer, David M. Society and Population. 2nd ed. Englewood Cliffs, New Jersey: Prentice-Hall, 1975.
Cita MLA (9th ed.)Heer, David M. Society and Population. 2nd ed. Prentice-Hall, 1975.
Atenció: Aquestes cites poden no estar 100% correctes.