@article{AM2_1994__47_2-3_137576,
     author = {Miroslav Chlebik and Josef Kr\'al},
     title = {Removability of the wave singularities in the plane.},
     journal = {Aequationes mathematicae},
     pages = {123--142},
     publisher = {mathdoc},
     volume = {47},
     number = {2-3},
     year = {1994},
     zbl = {0807.39009},
     url = {http://geodesic.mathdoc.fr/item/AM2_1994__47_2-3_137576/}
}