Study of Sulphate Origin in Shallow Groundwater in the Vicinity of Bantar Gebang-Bekasi Landfill Using Sulphur-34 and Oxygen-18 - Pujiindiyati, E.R.; Center for the Application of Isotope and Radiation Technology - BATAN Cinere Pasar Jum’at PO.Box 7002 JKSKL, Jakarta 12070, Indonesia (PPIKSN-BATAN, 2012)