Sidauruk, P. et al. 2016. Subsurface Flow and Surface Water Interactions Quantification in Gunung Kidul Karst Area Using Hydro- Chemical and Stable Isotopes Data Variations. Jurnal Ilmiah Aplikasi Isotop dan Radiasi. 11, 1 (Jan. 2016), 65–72. DOI:https://doi.org/10.17146/jair.2015.11.1.2700.