RAJU, K.VIJAYA, G. DAVID SUDHAKAR, and T. BENARJI PATRUDU. 2010. “Spectrophotometric Titration of Resorufin and Resazurinwith Iron(II) in Strong Phosphoric Acid Medium and Resorufin As a New Redox Indicator in the ReductimetricTitration of Some Metal Ions”. Asian Journal of Chemistry 19 (1):683-92. https://asianpubs.org/index.php/ajchem/article/view/20535.