Asymptotic theory Differential equations 4 Differential equations, Nonlinear 3 Differential equations, Linear 2 Asymptotic expansions 1 Bayesian versions 1 Bifurcation theory 1 Boundary value problems 1 Congresses 1 Differential equations, Elliptic 1 Differential operators.1 1 Integral equations 1 MATHEMATICS / Algebra / Abstract 1 Mathematical physics 1 Mathematical statistics 1 Nonlinear difference equations 1 Perturbation (Mathematics) 1 Qualitative theory 1 Stability 1 WKB approximation 1 Water waves 1 Wave-motion, Theory of 1