@ARTICLE\{IMM1993-0698,
    author       = "K. Madsen and H. B. Nielsen",
    title        = "A Finite Smoothing Algorithm for
Linear Estimation",
    year         = "1993",
    pages        = "223-235",
    journal      = "{SIAM} J. on Optimization",
    volume       = "3",
    editor       = "",
    number       = "",
    publisher    = "",
    url          = "http://www2.compute.dtu.dk/pubdb/pubs/698-full.html"
}