Riyanti, Riyanti, et al. “The The Acid-Base Indicator Paper of Extracted Ethanol from Ashoka Flower (Ixora Coccinea Linn) With Variances of Solvent and Soaking Period”. Jurnal Penelitian Pendidikan IPA, vol. 8, no. 4, Oct. 2022, pp. 1694-9, doi:10.29303/jppipa.v8i4.1494.