Sianipar, N. A.; Nurhayati, T.; Supari, S. Stability of Dielectric Insulation System in GSUT Transformer of Pertamina Geothermal Energy Lahendong: A Diagnostic Approach Based on DFR (Dielectric Frequency Response). Int. J. Adv. Technol. Eng. Inform. Syst. 2025, 4, 257-266.