@book{2554,
	author = { Perman, Roger. and Perman, Roger,},
	title = {Natural resource and environmental economics /},
	publisher = {Pearson Addison Wesley,},
	year = {c2011.},
	address = { New York:},
	edition = {4th ed.},
	note = {Prev. ed. entered under author: Perman, Roger, 1949-}
}