@book{69255,
	author = {La Investigación en el Colegio de Postgraduados y sus Perspectivas ( and Colegio de Postgraduados. Chapingo, Méx.},
	title = {Memoria.},
	publisher = {Colegio de Postgraduados,},
	year = {1989.},
	address = {Montecillo, Méx. :},
	note = {33-158}
}