@article{1153494551,
author = {Hirosawa, Fumihiko},
title = {Loss of regularity for second order hyperbolic equations with singular coefficients},
journal = {Osaka J. Math.},
volume = {42},
number = {1},
year = {2005},
pages = { 767-790},
language = {en},
url = {http://dml.mathdoc.fr/item/1153494551}
}
Hirosawa, Fumihiko. Loss of regularity for second order hyperbolic equations with singular coefficients. Osaka J. Math., Tome 42 (2005) no. 1, pp. 767-790. http://gdmltest.u-ga.fr/item/1153494551/