SMANOVA, Zulayxo, et al. “EXPRESS TEST METHOD FOR THE DETERMINATION OF CHROMIUM (VI) IONS WITH TWO SODIUM SALTS OF IMMOBILIZED 1,8-DIOXYNAPHTHALENINE-3,6-DISULPHIC ACID”. «ACTA NUUz», vol. 3, no. 3.1.1, Aug. 2026, pp. 491-3, http://journals.nuu.uz/index.php/actanuuz/article/view/14565.