M. Yasin, Uzair Noor, Sanaullah Tareen, Nasir Mahmood, Faheem Jan, and Mazhar Ali Khan, “Depression in Patients with Chronic Obstructive Pulmonary Disease at Tertiary Care Hospital of Khyber Pakhtunkhwa”, Pak J Chest Med, vol. 27, no. 1, pp. 08–13, Aug. 2021.