@article{Rudakov2016periodic,
author={Rudakov, I..},
title={PERIODIC SOLUTIONS PROBLEM OF HETEROGENEOUS STRING FORCED  OSCILLATIONS EQUATION WITH BOUNDARY CONDITION OF THE THIRD TYPE},
journal={Bulletin of Bryansk state technical university},
publisher={Bryansk State Technical University},
year={2016},
pages={99-107},
volume={2016},
issue={4},
}