LIMPONGSA, E., P. SRISUK, and N. JAIPAKDEE. “PREPARATION AND CHARACTERIZATION OF GRAPEFRUIT OIL BASE MICROEMULSIONS OF CAFFEINE”. International Journal of Applied Pharmaceutics, vol. 11, no. 2, Mar. 2019, pp. 231-8, doi:10.22159/ijap.2019v11i2.30958.