Gaya APA

Scmitz, G. et al (1981). Environmental Impact of Nonpoint Source Pollution . United States of America: Ann Arbor Science Publisher Inc The Butterworth Group.

Gaya MLA

Scmitz, Gery. et al. "Environmental Impact of Nonpoint Source Pollution". United States of America: Ann Arbor Science Publisher Inc The Butterworth Group, 1981. Text.