Immaniar, Dewi, Nur Azizah, Dedeh Supriyanti, Nanda Septiani, and Marviola Hardini. “PoTS: Proof of Tunnel Signature for Certificate Based on Blockchain Technology”. International Journal of Cyber ​​and IT Service Management (IJCITSM) 1, no. 1 (May 3, 2021): 101–114. Accessed October 13, 2025. https://iiast.iaic-publisher.org/ijcitsm/index.php/IJCITSM/article/view/28.