@article{1183513492,
author = {Bergman, Stefan},
title = {An initial value problem for a class of equations of mixed type},
journal = {Bull. Amer. Math. Soc.},
volume = {55},
number = {12},
year = {1949},
pages = { 165-174},
language = {en},
url = {http://dml.mathdoc.fr/item/1183513492}
}
Bergman, Stefan. An initial value problem for a class of equations of mixed type. Bull. Amer. Math. Soc., Tome 55 (1949) no. 12, pp. 165-174. http://gdmltest.u-ga.fr/item/1183513492/