ZBOINA, Bożena, DZIEDZIC, Ewelina, CUDZIK, Krzysztof, CZERWIŃSKA PAWLUK, Iwona and ZUKOW, Walery. Intensity of COPD symptoms in comparison with spirometry parameters. Journal of Education, Health and Sport. Online. 20 March 2019. Vol. 9, no. 3, pp. 409-423. [Accessed 17 July 2024].