In the paper it is proved that each generalized boundary value problem for the n-th order linear differential equation generates a Fredholm mapping of index zero.
@article{107524,
author = {Boris Rudolf},
title = {The generalized boundary value problem is a Fredholm mapping of index zero},
journal = {Archivum Mathematicum},
volume = {031},
year = {1995},
pages = {55-58},
zbl = {0830.34013},
mrnumber = {1342375},
language = {en},
url = {http://dml.mathdoc.fr/item/107524}
}
Rudolf, Boris. The generalized boundary value problem is a Fredholm mapping of index zero. Archivum Mathematicum, Tome 031 (1995) pp. 55-58. http://gdmltest.u-ga.fr/item/107524/
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