Popivanov, P. R. Local solvability of some classes of linear partial differential operators. (English) Zbl 0900.35085 Rend. Semin. Fac. Sci. Univ. Cagliari 64, No. 2, 173-186 (1994). MSC: 35G05 35A07 PDFBibTeX XMLCite \textit{P. R. Popivanov}, Rend. Semin. Fac. Sci. Univ. Cagliari 64, No. 2, 173--186 (1994; Zbl 0900.35085)
Bainov, D.; Kamont, Z.; Minchev, E. Numerical solutions of hyperbolic differential-functional equations with impulses. (English) Zbl 1126.35371 Rend. Semin. Fac. Sci. Univ. Cagliari 64, No. 2, 149-171 (1994). MSC: 35R10 35R12 65M99 PDFBibTeX XMLCite \textit{D. Bainov} et al., Rend. Semin. Fac. Sci. Univ. Cagliari 64, No. 2, 149--171 (1994; Zbl 1126.35371)