@article{Bec-Fli-Kac-Kaz-2021,
    author={Éliane Bécache and Sonia Fliss and Maryna Kachanovska and 
           Maria Kazakova },
    title={On a surprising instability result of Perfectly Matched Layers 
           for Maxwell's equations in 3D media with diagonal anisotropy },
    journal={Comptes Rendus. Mathématique },
    year={2021 },
    volume={3 },
    pages={249--256},
}