@book{9926,
	author = {Nicolás Santos, Rubén.},
	title = {Fecha óptima de amarre en lechuga (Lactuca sativa L.) variedad "Dark Green Cass" en Chapingo, Méx.},
	publisher = {El autor,},
	year = {1993},
	address = {Chapingo, Méx. :}
}