SAHU, K., et al. “Studies on Some Complexes of Cobalt (II) and Nickel(II) With Bis-(2-Hydroxyimino-1-Phenyl Propylidene)-1,4-Diamino Benzene”. Asian Journal of Chemistry, vol. 14, no. 3, June 2010, pp. 1541-4, https://asianpubs.org/index.php/ajchem/article/view/22435.