L. Lee and K. Abd Elnabi, “Freestanding Triboelectric-layer Mode Triboelectric Nanogenerator (TENG) via Rotating Circle”, IJIE, vol. 16, no. 3, pp. 133–144, May 2024, Accessed: Aug. 07, 2026. [Online]. Available: https://journal.uthm.edu.my/index.php/ijie/article/view/15857