Akhtar, P. M., Yardi, S., Tayade, B. O., Pathak, M. and Saraf, B. (2018) “Mental health, sleep and quality of life in patients with chronic obstructive pulmonary disease: a correlational study”, International Journal of Research in Medical Sciences, 6(6), pp. 2036–2041. doi: 10.18203/2320-6012.ijrms20182284.