Ningsih, G., and I. G. Sanjaya. “Determination of Calcium Levels With XRF and Literature Review of Its Bioavailability in Vitro of Dahlia Tubers Syrop (Dahlia Pinnata Cav.)”. Indonesian Journal of Chemical Science, Vol. 11, no. 2, July 2022, pp. 145-59, doi:10.15294/ijcs.v11i2.55945.