MUTUAL COORDINATION OF SYSTEMS BASED ON POLYMERIC STRUCTURES OF RARE-EARTH METAL IONS AND RATIONALE FOR THE STUDIES MUTUAL COORDINATION OF SYSTEMS BASED ON POLYMERIC STRUCTURES OF RARE-EARTH METAL IONS AND RATIONALE FOR THE STUDIES. ВНЮК. 2025;(2):17-22. doi:10.54251/2616-6429.2025.02.0003nu