M, M. et al. 2015. UTILIZATION OF CACAO FRUIT PEEL (Theobroma cacao) AS A BIOSORBENT OF Ni(II) IONS METAL. Jurnal Akta Kimia Indonesia (Indonesia Chimica Acta). 8, 1 (Jun. 2015), 31–41. DOI:https://doi.org/10.20956/ica.v8i1.2479.