2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/183319A self-contained description of algebraic structures, obtained by combinations of various limit procedures applied to vertex and face sl(2) elliptic quantum affine algebras, is given. New double Yangians structures of dynamical type are in particular defined. Connections between these structures are established. A number of them take the form of twist-like actions. These are conjectured to be evaluations of universal twists.42 pages, one Postscript figure; important reference added; some misprints corrected; definition of cladistics addedQuantum AlgebraMathematical Physics81R50; 17B37text