TY - JOUR AU - Fečkan, Michal AU - Kollár, Richard TI - Discontinuous wave equations and a topological degree for some classes of multi-valued mappings JO - Applications of Mathematics PY - 1999 SP - 15 EP - 32 VL - 44 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.1023/A:1022216119044/ DO - 10.1023/A:1022216119044 LA - en ID - 10_1023_A_1022216119044 ER -