@book{31979,
	author = {Cofer, Charles Norval and Appley, M.H.},
	title = {Psicología de la motivación  },
	publisher = {Trillas  },
	year = {1990.},
	series = {Biblioteca Técnica de psicología},
	address = {México },
	edition = {2a ed.},
	note = {Incluye índice}
}