@article{GDZPPN002069318,
title = {The nonlinear Klein-Gordon equation on an interval as a perturbed Sine-Gordon equation.},
journal = {Commentarii mathematici Helvetici},
volume = {70},
year = {1995},
pages = {63-112},
zbl = {0842.35099},
url = {http://dml.mathdoc.fr/item/GDZPPN002069318}
}
Bobenko, A.I.; Kuksin, Sergej B. The nonlinear Klein-Gordon equation on an interval as a perturbed Sine-Gordon equation.. Commentarii mathematici Helvetici, Tome 70 (1995) pp. 63-112. http://gdmltest.u-ga.fr/item/GDZPPN002069318/