MITU, L., et al. “Synthesis and Characterization of Cu(II), Ni(II), Co(II), Mn(II), Zn(II), Cd(II) Complexes of Isonicotinoylhydrazone-1-Methyl-2-Aldehydepyrrole”. Asian Journal of Chemistry, vol. 19, no. 7, Mar. 2010, pp. 5666-74, https://asianpubs.org/index.php/ajchem/article/view/13183.