@book{99990,
	author = {Kuhn, Thomas S.  and Helier, Roberto and Consejo Nacional de Ciencia y Tecnología },
	title = {La tensión esencial : },
	publisher = {Fondo de Cultura Económica, },
	year = {c1982.},
	address = {Madrid : },
	note = {Título original: The essential tension : selected studies in scientific tradition and change.}
}