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
"Dreher, Michael","Weakly hyperbolic equations, Sobolev spaces of variable order, and propagation of singularities",,"Institute of Mathematics, University of Tsukuba",2000,Mathematical research note,,,,https://cir.nii.ac.jp/crid/1130000796324937984