Dwikarlina, Intan, et al. “Grade V Subcutaneous Emphysema in a Patient With Recurrent Secondary Spontaneous Pneumothorax: A Case Report”. Jurnal Klinik Dan Riset Kesehatan, vol. 3, no. 1, Oct. 2023, pp. 64-72, https://doi.org/10.11594/jk-risk.03.1.8.