“DETERMINATION OF CHROMIUM (VI) BY MEANS OF AMPEROMETRIC TITRATION METHOD USING TETRAMETHYLTHIONIN”, Proc. YSU B: Chem. Biol. Sci., vol. 43, no. 2 (219), pp. 65–67, May 2009, doi: 10.46991/PYSUB.2009.43.2.065.