Yusuf, F., A. Prasetyo, V. Karlowee, M. D. K. Astuti, and R. W. Nur. “Increased Expression of PD-L1 in Undifferentiated Non Keratinizing Squamous Cell Carcinoma Nasopharynx”. Medica Hospitalia : Journal of Clinical Medicine, vol. 8, no. 2, July 2021, pp. 200-6, doi:10.36408/mhjcm.v8i2.579.