“A Study of the Mechanisms of Adsorption of Nickel Ions by Different Types of Soils in Udmurtia”. Sorbtsionnye I Khromatograficheskie Protsessy, vol. 20, no. 5, Nov. 2020, pp. 594-01, https://doi.org/10.17308/sorpchrom.2020.20/3052.