1997, Volume 213

The collection consists of ten papers on Differential Equations Qualitative Theory. The difference of subjects reflects sometimes unexpected inner relations running through this theory. The nonlinear analog of Riemann–Hilbert problem, the analytic classification of complex singular points and the description of phase portraits of polynomial vector fields near the infinite line on the complex projective plane – all these subjects are closely related to properties of groups of germs of conformai mappings. These problems are considered in the first four papers. The global investigations of the phase curves of holomorphic differential equations regarded as Riemann surfaces are carried out in the next two papers. The new version of the concept “almost everywhere” for nonlinear functional spaces is introduced in the 7th paper. Basic results of the singularity theory and ordinary differential equations are revised from the point of view related to this concept. 8th and 9th papers are dedicated to investigation of nonlocal bifurcations in generic two- and three-parametrical families of planar vector fields. 10th paper is dedicated to investigation of the center-focus problem in its modern formulation.
The collection is recommended to post-graduates and researchers in Differential Equations, Bifurcations Theory and Complex Analysis.

ISBN: 5-02-003701-Х
UDC: 517.9+517.5