We shall give a new proof of the admissibility of singular perturbations, which was introduced by the author , without the assumption on the characteristic roots assumed in  using the method introduced by the author in [5, Appendix].
Cite this article
Ryuichi Ashino, On the Admissibility of Singular Perturbations in Cauchy Problems II. Publ. Res. Inst. Math. Sci. 30 (1994), no. 6, pp. 1039–1054DOI 10.2977/PRIMS/1195164947