@article{molnar2016analytical,
    title={Analytical estimations of limit cycle amplitude for delay-differential equations},
    author={Molnar, Tamas G and Insperger, Tamas and Stepan, Gabor},
    journal={Electronic Journal of Qualitative Theory of Differential Equations},
    volume={2016},
    number={77},
    pages={1--10},
    year={2016},
    publisher={University of Szeged, Hungary},
    doi={10.14232/ejqtde.2016.1.77}
}