Felicio-Júnior, Egberto Luiz, et al. “Randomized Trial of Physiotherapy and Hypertonic Saline Techniques for Sputum Induction in Asthmatic Children and Adolescents”. Clinics, vol. 75, Feb. 2020, p. e1512, https://doi.org/10.6061/clinics/2020/e1512.