@article{BUMI_1999_8_2B_1_a2,
     author = {Gramchev, Todor and Rodino, Luigi},
     title = {Gevrey solvability for semilinear partial differential equations with multiple characteristics},
     journal = {Bollettino della Unione matematica italiana},
     pages = {65--120},
     publisher = {mathdoc},
     volume = {Ser. 8, 2B},
     number = {1},
     year = {1999},
     zbl = {0924.35030},
     mrnumber = {1172111},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/BUMI_1999_8_2B_1_a2/}
}