C. Bisaccioni, M. V. Aun, E. Cajuela, J. Kalil, R. C. Agondi, and P. Giavina-Bianchi, “ Comorbidities in severe asthma: frequency of rhinitis, nasal polyposis, gastroesophageal reflux disease, vocal cord dysfunction and bronchiectasis ”, Clinics, vol. 64, no. 8, pp. 769–773, Jan. 2009, doi: 10.1590/S1807-59322009000800010.