SUBBAYAMMA, A.V., and C. RAMBABU. “Cobalt Thiocyanate As Chromogenic Reagent for Determination of Trandolapril and Aripiprazole”. Asian Journal of Chemistry, vol. 21, no. 6, Mar. 2010, pp. 4285-8, https://asianpubs.org/index.php/ajchem/article/view/18162.