@booklet {,
	title = {Geol{\'o}gia del cuadrangulo de Cailloma, Hoja 31-s},
	year = {1988},
	publisher = {Instituto Geol{\'o}gico Minero y Metal{\'u}rgico},
	address = {scale 1:100,000},
	author = {Davila M. , David}
}