@ARTICLE\{IMM2004-0545,
    author       = "A. A. Antonov and P. G. Thomsen and Z. Zlatev",
    title        = "Phase and Group Velocities of {2D} Numerical Approximations for Hyperbolic Equations",
    year         = "2004",
    keywords     = "Hyperbolic {PDE'}s , Numerical Approximations , Phase velocities, Group velocities",
    journal      = "Computational Methods in Applied Mathematics",
    volume       = "",
    editor       = "",
    number       = "",
    publisher    = "",
    url          = "http://www2.compute.dtu.dk/pubdb/pubs/545-full.html"
}