Zakaria, Rosnah, et al. “Comparison of Conductivity Performance of Dragon Fruit Dye Extracted Using Water and Ethanol for Dye Sensitized Solar Cells”. International Journal of Engineering & Technology, vol. 7, no. 3.11, July 2018, pp. 126-8, https://doi.org/10.14419/ijet.v7i3.11.15944.