D.GOPALA KRISHNA, et al. “DIRECT AND DERIVATIVE SPECTROPHOTOMETRIC DETERMINATION OF CADMIUM (II) IN PRESENCE OF MICELLAR MEDIUM IN BIOLOGICAL MATERIALS AND IN ALLOY SAMPLES USING CINNAMALDEHYDE-4- HYDROXY BENZOYLHYDRAZONE (CMHBH)”. International Journal of Pharma and Bio Sciences, vol. 1, no. 3, Sept. 2010, pp. 1-19, https://ijpbs.net/index.php/journal/article/view/173.