K.RAJASEKAR, and T.RAMACHANDRAMOORTHY. “SYNTHESIS, SPECTRAL CHARACTERIZATION AND BIOLOGICAL ACTIVITIES OF Cr(III), Co(II), Ni(II) AND Cd(II) COMPLEXES WITH 4-AMINOANTIPYRINE AND THIOCYANATE ION AS LIGANDS”. International Journal of Pharma and Bio Sciences, vol. 4, no. 2, June 2013, pp. 271-6, https://ijpbs.net/index.php/journal/article/view/2170.