@article{SEDP_1993-1994____A19_0,
     author = {Colombini, F. and Lerner, N.},
     title = {Hyperbolic operators with non {Lipschitz} coefficients},
     journal = {S\'eminaire Goulaouic-Schwartz},
     note = {talk:18},
     pages = {1--12},
     year = {1993-1994},
     publisher = {Ecole Polytechnique, Centre de Math\'ematiques},
     mrnumber = {1300914},
     zbl = {0922.35084},
     language = {en},
     url = {https://www.numdam.org/item/SEDP_1993-1994____A19_0/}
}