@article{ASNSP_1995_4_22_3_469_0,
     author = {D'Ancona, Piero and Spagnolo, Sergio},
     title = {Small analytic solutions to nonlinear weakly hyperbolic systems},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {469--491},
     publisher = {Scuola normale superiore},
     volume = {Ser. 4, 22},
     number = {3},
     year = {1995},
     mrnumber = {1360546},
     zbl = {0858.35079},
     language = {en},
     url = {http://www.numdam.org/item/ASNSP_1995_4_22_3_469_0/}
}