Porosity Analysis of Limestone in the South Leato Region of Gorontalo City Aang Panji Permana, Sunarty Suly Eraku, Ronal Hutagalung and Rini Rahmatia Suarno E3S Web Conf., 400 (2023) 01010 Published online: 03 July 2023 DOI: 10.1051/e3sconf/202340001010