Dyfyniad APA

Simmons, I. (1991). Earth, air and water: Resources and environment in the late 20th century. Edward Arnold.

Dyfyniad Arddull Chicago

Simmons, I.G. Earth, Air and Water: Resources and Environment in the Late 20th Century. London: Edward Arnold, 1991.

Dyfyniad MLA

Simmons, I.G. Earth, Air and Water: Resources and Environment in the Late 20th Century. Edward Arnold, 1991.

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