Bogoyavlenskij, Oleg I. Courant’s problems and their extensions. (English) Zbl 0926.35082 Fey, Michael (ed.) et al., Hyperbolic problems: Theory, numerics, applications. Proceedings of the 7th international conference, Zürich, Switzerland, February 1998. Vol. I. Basel: Birkhäuser. ISNM, Int. Ser. Numer. Math. 129, 97-104 (1999). The paper discusses the Courant problems for the first-order hyperbolic systems of partial differential equations. New geometric invariants are defined for these systems. Applications of these invariants to the Courant problems are presented. Applications to the gas dynamics equations, Benney equations, and their perturbations are developed.For the entire collection see [Zbl 0911.00028]. Reviewer: P.Y.Yalamov (Russe) Cited in 3 Documents MSC: 35L60 First-order nonlinear hyperbolic equations Keywords:new geometric invariants; gas dynamics equations; Benney equations PDFBibTeX XMLCite \textit{O. I. Bogoyavlenskij}, ISNM, Int. Ser. Numer. Math. 129, 97--104 (1999; Zbl 0926.35082)