A necessary condition in the monodromy problem for analytic differential equations on the plane
In this paper we give a very easy to compute necessary condition in the monodromy problem for all singular point of analytic differential systems in the real plane. Our main tool is considering the analytic function, angular speed, and studying its limit through straight lines to the singular point. (c) 2006 Elsevier Ltd. All rights reserved.
monodromy problem planar vector field characteristic orbit