K. D. Sasmita, I. Anas, S. Anwar, S. Yahya, and G. Djajakirana, “Application of Biochar and Organic Fertilizer on Acid Soil as Growing Medium for Cacao (Theobroma cacao L.) Seedlings”, IJSBAR, vol. 36, no. 5, pp. 261–273, Nov. 2017.