Aryani, T., and I. Mu’awanah. “Antioxidant Activity and Vitamin C Levels of Fruit Flesh and Dragon (Hylocereus Costaricensis) Fruit Syrup”. Biomedika, Vol. 12, no. 2, Sept. 2019, pp. 149-57, doi:https://doi.org/10.31001/biomedika.v12i2.592.