@book{4197,
	author = {Caballero Armas, Wilfredo},
	title = {Introducción a la estadística},
	publisher = {IICA,},
	year = {1981},
	series = {IICA: Serie de Libros y Materiales Educativos, 28},
	address = {San José, Costa Rica:},
	edition = {1a. ed.}
}