Invited papers 1
Differential geometry as a tool for applied mathematicians&F.B.Estabrook 1
Some Heuristic Comments on Solitons，Integrability Conditions and Lie Groups&J.Corones 23
On Backlund transformations and solu-tions to the 2＋1 and 3＋1-dimensional sine-Gordon equation&P.L.Christiansen 43
Backlund transformations&R.K.Dodd and H.C.Morris 63
Generalised Backlund transformations for integrable evolution equations associated with Nth order scattering problems&R.K.Dodd and H.C.Morris 95
Meromorphic forms solutions of completely integrable pfaffian systems with regular singularities&R.Gerard 99
Far fields，nonlinear evolution equations，the Backlund transformation and inverse scattering&A.Jeffrey 118
Convergence of formal power series solu-tions of a system of nonlinear differential equations at an irregular singular point&Y.Sibuya 135
Contributed papers 143
Non-linear wave equations as Hamiltonian systems&L.J.F.Broer 143
How many jumps？Variational characteriza-tion of the limit solution of a singular perturbation problem&O.Diekman and D.Hilhorst 159
The continuous Newton-method for mero- morphic functions&H.Th.Jongen， P.Jonker and F.Twilt 181
A precise definition of separation of variables&T.H.Koornwinder 240
Generation of limit cycles from separatrix polygons in the phase plane&J.W.Reyn 264
Normal solvability for linear partial dif-ferential operators in C∞ （Ω）&B.Sagraloff 290
Connection problems for linear ordinary differential equations in the complex domain&R.Schafke and D.Schmidt 306
Periodic solutions of continuous self-gravitating systems&F.Verhulst 318