文 献 [20] A. Kaneko, On continuation of regular soluti ons of partial differential equations to compact convex sets, J. Fac. Sci. Univ. Tokyo, 17 (1970), 567-580.-, Ibid. II. Ibid .,18(1971),416-433. [21) -,Fundamental principle and extension of solutions of partial differential equations with constant coefficients, Hyperfunctions and Pseudo- differential Equations, Part I, Proceedings of a Conference at Katada,1971, Springer, Lecture Notes in Mathematics, to appear.
