@article{oai:repository.dl.itc.u-tokyo.ac.jp:00039398, author = {Ishii, Tan}, issue = {2}, journal = {Journal of the Faculty of Science, the University of Tokyo. Sect. 1 A, Mathematics = 東京大学理学部紀要. 第1類A, 数学}, month = {}, note = {application/pdf}, pages = {377--424}, title = {On propagation of regular singularities for solutions of nonlinear partial differential equations}, volume = {37}, year = {1990} }