Existence and uniqueness of the solution to a fourth order nonlinear vector periodic boundary value problem is proved by using the estimates for derivatives of the Green function for the corresponding homogenous scalar problem
@article{107489,
author = {\v Ludov\'\i t Pinda},
title = {On a fourth order periodic boundary value problem},
journal = {Archivum Mathematicum},
volume = {030},
year = {1994},
pages = {1-8},
zbl = {0808.34020},
mrnumber = {1282107},
language = {en},
url = {http://dml.mathdoc.fr/item/107489}
}
Pinda, Ľudovít. On a fourth order periodic boundary value problem. Archivum Mathematicum, Tome 030 (1994) pp. 1-8. http://gdmltest.u-ga.fr/item/107489/
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