@article{1077475206,
author = {Ingersoll, Benham M.},
title = {The regularity domains of solutions of linear partial
differential equations in terms of the series development of
the solution},
journal = {Duke Math. J.},
volume = {15},
number = {1},
year = {1948},
pages = { 1045-1056},
language = {en},
url = {http://dml.mathdoc.fr/item/1077475206}
}
Ingersoll, Benham M. The regularity domains of solutions of linear partial
differential equations in terms of the series development of
the solution. Duke Math. J., Tome 15 (1948) no. 1, pp. 1045-1056. http://gdmltest.u-ga.fr/item/1077475206/