Dyfyniad APA

HARTWICK, J. M., & OLEWILER, N. D. (1986). The economics of natural resource use. Harper and Row.

Dyfyniad Arddull Chicago

HARTWICK, John M., and Nancy D. OLEWILER. The Economics of Natural Resource Use. Cambridge: Harper and Row, 1986.

Dyfyniad MLA

HARTWICK, John M., and Nancy D. OLEWILER. The Economics of Natural Resource Use. Harper and Row, 1986.

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