Cita APA (7th ed.)

Koch, P. (2010). Water sources (4th ed.). American Water Works Association.

Cita Chicago (17th ed.)

Koch, Paul. Water Sources. 4th ed. Denver, Colo.: American Water Works Association, 2010.

Cita MLA (9th ed.)

Koch, Paul. Water Sources. 4th ed. American Water Works Association, 2010.