Nguyen, Cong Thinh, and C. Ngoc Le. “Utilizing Layer-2 Blockchain and IPFS Innovations for Establishing a Robust System for Secure Document Signing and Management”. JST: Smart Systems and Devices 34, no. 2 (May 15, 2024): 44–53. Accessed June 18, 2025. https://jst.vn/index.php/ssad/article/view/77.