“Bis-Indolylmethane Derivatives As A Potential Colorimetric Sensor for Chromium Ion Detection in Water”. Borneo Engineering & Advanced Multidisciplinary International Journal, vol. 3, no. Special Issue (ICo-ASCNITech 2024), Sept. 2024, pp. 10-16, https://beam.pmu.edu.my/index.php/beam/article/view/182.