Khatkar, S.P., et al. “Ethanethioic Acid As a Reagent for Trace Determination of Zn(II), Cd(II) and Hg(II)”. Asian Journal of Chemistry, vol. 16, no. 1, Mar. 2010, pp. 549-51, https://asianpubs.org/index.php/ajchem/article/view/19692.