U. A. Muhammad, L. G. Tham, N. Perumal, H. M. Daud, N. A. Yasid, and M. Y. Shukor, “Assay for heavy metals using an inhibitive assay based on the acetylcholinesterase from Clarias batrachus”, Bioremed Sci Technol Res, vol. 4, no. 2, pp. 6–10, Dec. 2016.