GUNEN, Hakan, and Feridun KOSAR. “Role of Systemic Corticosteroids In Moderate And Severe COPD”. Annals of Medical Research 7, no. 3 (May 25, 2021): 0202–0206. Accessed May 20, 2024. http://www.annalsmedres.org/index.php/aomr/article/view/2808.