Paembonan, A. Y., and F. D. W. Waruwu. “Subsurface Utility Identification at ITERA Campus Using Multi-Frequency Ground Penetrating Radar”. Jurnal Teori Dan Aplikasi Fisika, vol. 12, no. 1, Jan. 2024, pp. 93-102, doi:10.23960/jtaf.v12i1.349.