“THE IMPACTS OF MT. SEMERU VOLCANIC ASH ON THE NEARBY AGRICULTURAL LAND FERTILITY: A CASE STUDY OF APPLICATION OF BORE-HOLE AND GEOELECTRIC METHODS” (2023) GEOMATE Journal, 25(111), pp. 57–65. Available at: https://geomatejournal.com/geomate/article/view/3953 (Accessed: 19 April 2026).