@book{121797,
	author = {Pera, Marcello,},
	title = {The ambiguous frog :},
	publisher = {Princeton University Press,},
	year = {c1992.},
	address = {Princeton, N.J. :},
	note = {Translation of: La rana ambigua.},
	url = {http://www.loc.gov/catdir/description/prin031/91003077.html}
}