Jakubowska, K. O., A. Sykut, M. Łopuszyńska, B. Kropornicka, and A. Kościołek. “Life Quality of Patients With Chronic Obstructive Pulmonary Disease”. Journal of Education, Health and Sport, vol. 7, no. 9, Aug. 2017, pp. 33-44, https://apcz.umk.pl/JEHS/article/view/4750.