@article{Yevstafyeva_2021, title={Existence of two-point oscillatory solutions of a relay nonautonomous system with a multiple eigenvalue of a real symmetric matrix}, volume={73}, url={https://umj.imath.kiev.ua/index.php/umj/article/view/6379}, DOI={10.37863/umzh.v73i5.6379}, abstractNote={<p>UDC 517.925</p> <p>We study an $n$-dimensional system of ordinary differential equations with a hysteresis type relay nonlinearity and a periodic perturbation function in the right-hand side.<br>It is supposed that the matrix of the system is real and symmetric and it has an eigenvalue of multiplicity two.<br>In the phase space of the system, we consider continuous bounded oscillatory solutions with two fixed points and the same return time to each of these points.<br>For such solutions, we prove the existence and nonexistence theorems.<br>These results are illustrated by a numerical example for a three-dimensional system.</p&gt;}, number={5}, journal={Ukrains’kyi Matematychnyi Zhurnal}, author={Yevstafyeva , V. V.}, year={2021}, month={May}, pages={640 - 650} }