@article{01225580,
title = {Sound wave fronts of plane curves. II. (Schallfronten an ebenen Kurven. II.)},
journal = {Mathematica Pannonica},
volume = {9},
year = {1998},
pages = {17-31},
zbl = {0905.53004},
language = {en},
url = {http://dml.mathdoc.fr/item/01225580}
}
Sachs, Hans; Suda Karáné, Gizella. Sound wave fronts of plane curves. II. (Schallfronten an ebenen Kurven. II.). Mathematica Pannonica, Tome 9 (1998) pp. 17-31. http://gdmltest.u-ga.fr/item/01225580/