Chavan, J.D., and V.P. Joshi. “Spectrophotometric Determination of Micro Amounts of Gold(III) Using Cyclopentane-Spiro-2´ -(1-Methyl-2´ ,4&Acute; -Dithio)-S-Triazine ”. Asian Journal of Chemistry, vol. 4, no. 2, Mar. 2010, pp. 361-3, https://asianpubs.org/index.php/ajchem/article/view/25051.