@book{293982,
	author = {Polit, Denise F. and Hungler, Bernadette P.},
	title = {Investigación científica en ciencias de la salud / Denise F. Polit,  Bernadette P. Hungler},
	publisher = {Mcgraw-Hill Interamericana},
	year = {1991},
	address = {Mexico},
	edition = {3a ed.}
}