Chernozubova Ekaterina Viktorovna RussiaSaratovSSU. Institute of Chemistry. Department of General and Inorganic Chemistry, 410012, Saratov, Astrakhanskaya srt., 83, building. 1, Institute of Chemistry, SSUkkapustina@mail.ru Author's articles Multivariate Regression Methods for Simultaneous Сatalimetry Determination of Iridium (IV) and Rhodium (III) Sensor Plate in Horseradish Peroxidase Determination Based on Oxidation of Triphenylamine-4-sulphonic Acid by Hydrogene Peroxide