TY - JOUR AU - V. Kostin TI - On the problem of symmetrization of hyperbolic equations JO - Banach Center Publications PY - 1992 SP - 257 EP - 269 VL - 27 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.4064/-27-1-257-269/ DO - 10.4064/-27-1-257-269 LA - en ID - 10_4064__27_1_257_269 ER -