S. Thunoon, E., and N. H. Shekho. “Improved Spectrophotometric Determination of Bismuth (III) With Bromopyrogallol Red in Mixed Surfactants-Application to Waters and Veterinary Preparation”. Rafidain Journal of Science, vol. 24, no. 3, Mar. 2013, pp. 39-52, doi:10.33899/rjs.2013.71038.