“Synthesis and Characterization of Silica Covalently Immobilized With Azohydrazon (formazan) Groups for Recovery of Noble Metals”. Sorbtsionnye i Khromatograficheskie Protsessy 14, no. 3 (November 19, 2019). Accessed April 5, 2026. https://journals.vsu.ru/sorpchrom/article/view/1493.