@book{137150,
	author = {National Petrochemical & Refiners Association, NPRA},
	title = {Sitio Web Institucional},
	publisher = {National Petrochemical & Refiners Association, NPRA},
	year = {2002},
	address = {Washington},
	note = {Sitio Web visitado en julio de 2002. ; Navegadores de Internet},
	url = {http://www.npradc.org/}
}