Cita APA (7th ed.)

Heller, R. L. (1979). Earth science (2d ed.). Webster Division, McGraw-Hill.

Cita Chicago (17th ed.)

Heller, Robert L. Earth Science. 2d ed. New York: Webster Division, McGraw-Hill, 1979.

Cita MLA (9th ed.)

Heller, Robert L. Earth Science. 2d ed. Webster Division, McGraw-Hill, 1979.