@ARTICLE\{IMM2000-01922,
    author       = "A. T. Andersen and M. F. Neuts and B. F. Nielsen",
    title        = "PH-distributions arising through
 conditioning",
    year         = "2000",
    pages        = "179-188",
    journal      = "Communications in statistics - Stochastic models",
    volume       = "16",
    editor       = "",
    number       = "1",
    publisher    = "",
    url          = "http://www2.compute.dtu.dk/pubdb/pubs/1922-full.html"
}