Compatibility of systems of linear ordinary differential equations with variable coefficients.
(English).
In:
Greguš, Michal (ed.):
Equadiff 5.
Proceedings of the Fifth Czechoslovak Conference on Differential Equations and Their Applications held in Bratislava, August 24-28, 1981.
BSB B.G. Teubner Verlagsgesellschaft, Leipzig, 1982.
pp. 235-236