Anna Fadliah Rusydi, Shin-ichi Onodera, Mitsuyo Saito, Seiichiro Ioka and Rizka Maria 2019. ESTIMATION OF AMMONIUM SOURCES IN INDONESIAN COASTAL ALLUVIAL GROUNDWATER USING Cl- AND GIS. GEOMATE Journal. 17, 62 (Oct. 2019), 53–58.