Dyfyniad APA

Audesirk, T., Audesirk, G., & Byers, B. E. (2000). Life on earth: Study guide (2nd ed.). Prentice Hall.

Dyfyniad Arddull Chicago

Audesirk, Teresa, Gerald Audesirk, and Bruce E. Byers. Life on Earth: Study Guide. 2nd ed. Upper Saddle River, N.J: Prentice Hall, 2000.

Dyfyniad MLA

Audesirk, Teresa, et al. Life on Earth: Study Guide. 2nd ed. Prentice Hall, 2000.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.