Ai. Bobenko et Sb. Kuksin, SMALL-AMPLITUDE SOLUTIONS OF THE SINE-GORDON EQUATION ON AN INTERVAL UNDER DIRICHLET OR NEUMANN BOUNDARY-CONDITIONS, Journal of nonlinear science, 5(3), 1995, pp. 207-232
We give a complete classification of the small-amplitude finite-gap so
lutions of the sine-Gordon (SG) equation on an interval under Dirichle
t or Neumann boundary conditions. Our classification is based on an an
alysis of the finite-gap solutions of the boundary problems for the SG
equation by means of the Schottky uniformization approach.