@book{17978,
	author = {Puchta, Herbert and Schratz, Michael},
	title = {Teaching teenagers},
	publisher = {Addison Wesley Longman},
	year = {1996},
	series = {Longman handbooks for language teachers},
	address = {Harlow},
	edition = {3ª ed.},
	note = {Contiene índice alfabético}
}