SUSHAMA, P.G., and M. ALAUDEEN. “Synthetic, Spectral and Antibacterial Studies of Co(III) and Mn(III) Metal Chelates of 2,5-Dihydroxy Undecyl 1,4-Benzoquinone and Its Azo Derivatives ”. Asian Journal of Chemistry, vol. 15, no. 1, Mar. 2010, pp. 366-72, https://asianpubs.org/index.php/ajchem/article/view/21576.