Syfridiana, Rafina, and Fauna Herawati. “Roflumilast: Review of Phosphodiesterase-4 Inhibitor As Asthma Therapy”. Journal of Health Sciences 14, no. 3 (August 29, 2021): 214–221. Accessed May 3, 2024. https://journal2.unusa.ac.id/index.php/JHS/article/view/2114.