2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/17875Resonant mode interactions in weakly nonlinear multi-dimensional lattices and related effects are described. We concentrate on formal description of the phenomenon and consider as examples mode interactions and evolution equations for quadratic solitons in two-dimensional lattices, and coherent structures in a double-chain as examples of the application of the theory.To appear in "Nonlinearity and Disorder: Theory and Applications" Eds. F. Kh. Abdullaev, O. Bang, M. P. Soerensen (Kluwer Academic Publishers, 2001)Statistical Mechanicstext