TY  - JOUR
AU  - Müller zum Hagen, H.
TI  - Characteristic initial value problem for hyperbolic systems of second order differential equations
JO  - Annales de l'I.H.P. Physique théorique
PY  - 1990
SP  - 159
EP  - 216
VL  - 53
IS  - 2
PB  - Gauthier-Villars
UR  - http://www.numdam.org/item/AIHPA_1990__53_2_159_0/
LA  - en
ID  - AIHPA_1990__53_2_159_0
ER  -