@inbook{Jol-Tso-2008-2,
    author={Patrick Joly and Chrysoula Tsogka },
    title={Finite element methods with discontinuous displacement. 
           ``Effective
computational methods for wave propagation'', },
    publisher={Chapman & Hall/CRC },
    year={2008 },
    volume={5 },
    series={Numer. Insights, },
    pages={331--357},
}