Dyfyniad APA

Field,Barry C, & Field,Martha K. (2002). Environmental economics: An introduction (3.). McGraw Hill.

Dyfyniad Arddull Chicago

Field,Barry C, and Field,Martha K. Environmental Economics: An Introduction. 3. New York: McGraw Hill, 2002.

Dyfyniad MLA

Field,Barry C, and Field,Martha K. Environmental Economics: An Introduction. 3. McGraw Hill, 2002.

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