@article{1195517000,
author = {Igari, Katsuju},
title = {Cauchy problem for hyperbolic differential operators with double characteristic roots},
journal = {Proc. Japan Acad. Ser. A Math. Sci.},
volume = {56},
number = {2},
year = {1980},
pages = { 67-69},
language = {en},
url = {http://dml.mathdoc.fr/item/1195517000}
}
Igari, Katsuju. Cauchy problem for hyperbolic differential operators with double characteristic roots. Proc. Japan Acad. Ser. A Math. Sci., Tome 56 (1980) no. 2, pp. 67-69. http://gdmltest.u-ga.fr/item/1195517000/