Riyanto, C. A.; Ampri, M. S.; Martono, Y. Synthesis and Characterization of Nano Activated Carbon from Annatto Peels (Bixa Orellana L.) Viewed from Temperature Activation and Impregnation Ratio of H3PO4. EKSAKTA: J. Sci. Data Anal. 2020, 20, 44-50.