Geometrical Approaches to Differential Equations: Proceedings of the Fourth Scheveningen Conference on Differential Equations, The Netherlands August 26 – 31, 1979

Differential geometry as a tool for applied mathematicians....Pages 1-22 Some heuristic comments on solitons, integrability conditions and lie groups....Pages 23-42 On Bäcklund transformations and solutions to the 2+1 and 3+1 - dimensional sine — Gordon equation....Pages 43-62 Bäcklund transformations....Pages 63-94 Generalised Bäcklund transformations for integrable evolution equations associated with Nth order scattering problems....Pages 95-98 Meromorphic forms solutions of completely integrable Pfaffian systems with regular singularities....Pages 99-117 Far fields, nonlinear evolution equations, the Bäcklund transformation and inverse scattering....Pages 118-134 Convergence of formal power series solutions of a system of nonlinear differential equations at an irregular singular point....Pages 135-142 Non-linear wave equations as hamiltonian systems....Pages 143-158 How many jumps? Variational characterization of the limit solution of a singular perturbation problem....Pages 159-180 The continuous Newton-method for meromorphic functions....Pages 181-239 A precise definition of separation of variables....Pages 240-263 Generation of limit cycles from separatrix polygons in the phase plane....Pages 264-289 Normal solvability of linear partial differential operators in C ∞ (Ω)....Pages 290-305 Connection problems for linear ordinary differential equations in the complex domain....Pages 306-317 Periodic solutions of continuous self-gravitating systems....Pages 318-339