著者名,書名,版表示,出版者名,出版年,シリーズ名,番号,ISBN,ISSN,URL "Colombini, F. (Ferruccio) and 木下, 保",On the Gevrey wellposedness of the Cauchy problem for weakly hyperbolic equations of higher order,,"Institute of Mathematics, University of Tsukuba",2000,Mathematical research note,,,,https://cir.nii.ac.jp/crid/1130282271925992576