Aswanetmane, P., and C. Limsuwat. “Obstructive Sleep Apnea in Patients With Chronic Obstructive Pulmonary Disease”. The Southwest Respiratory and Critical Care Chronicles, Vol. 2, no. 7, July 2014, pp. 41-45, https://pulmonarychronicles.com/index.php/pulmonarychronicles/article/view/146.