Maulani, G., Gunawan, G., Leli, L., Ayu Nabila, E. . and Yestina Sari, W. . (2021) “Digital Certificate Authority with Blockchain Cybersecurity in Education”, International Journal of Cyber ​​and IT Service Management (IJCITSM), 1(1), pp. 136–150. doi: 10.34306/ijcitsm.v1i1.40.