Sergey Kryzhevich
Universitetsky prospekt, 28,
198504, Peterhof, St. Petersburg, Russia,
Saint-Petersburg State University,
The Faculty of Mathematics and Mechanics,
Differential Equations Department
A single-degree-of-freedom system, sutured from two second order linear equations, is studied. For simple periodic solutions of such kind of systems, the structure of Perron manifolds is described and sufficient conditions are given.