@article{ASNSP_1983_4_10_2_291_0,
     author = {Colombini, F. and Jannelli, E. and Spagnolo, S.},
     title = {Well-posedness in the {Gevrey} classes of the {Cauchy} problem for a non-strictly hyperbolic equation with coefficients depending on time},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {291--312},
     publisher = {Scuola normale superiore},
     volume = {Ser. 4, 10},
     number = {2},
     year = {1983},
     mrnumber = {728438},
     zbl = {0543.35056},
     language = {en},
     url = {http://www.numdam.org/item/ASNSP_1983_4_10_2_291_0/}
}