@book{2817,
	author = {Acosta Lizarazo, Juan G., and Navas Álvarez, Jaime},
	title = {Análisis Agroeconómico de la Fertilización en Cultivos :},
	publisher = {Instituto Colombiano Agropecuario. ICA,},
	year = {1978.},
	address = {Tibaitata :}
}