Juraev M.M, Botirov S.Kh, and Khushvaqtov S.Y, “SEPARATION OF Cu (II) AND Ni (II) IONS FROM TECHNOLOGICAL SOLUTIONS USING POLYVINYL CHLORIDEBASED ION EXCHANGER”, Euro. J. Agri. Rur. Edu., vol. 3, no. 7, pp. 8-10, Jul. 2022.