Bellone, A., Motta, L., Etteri, M., Bianchi, A. M., Cappelletti, A., Bossi, I., Guanziroli, M., Pina, P. and Colombo, L. (2014) “Ventimask in exacerbation of chronic obstructive pulmonary disease and mild acidosis before starting with bilevel positive airway pressure”, Emergency Care Journal, 10(2). doi: 10.4081/ecj.2014.3754.