@article{AIHPC_1994__11_4_343_0,
     author = {D'Ancona, Piero},
     title = {The {Cauchy} problem for semilinear weakly hyperbolic equations in {Hilbert} spaces},
     journal = {Annales de l'I.H.P. Analyse non lin\'eaire},
     pages = {343--358},
     publisher = {Gauthier-Villars},
     volume = {11},
     number = {4},
     year = {1994},
     mrnumber = {1287237},
     zbl = {0836.34064},
     language = {en},
     url = {http://www.numdam.org/item/AIHPC_1994__11_4_343_0/}
}