@ARTICLE\{IMM1990-02571,
    author       = "C. K. Hansen and P. Thyregod",
    title        = "Estimation of the Mean Cumulative Number of Failures in a Repairable System with Mixed Exponential Lifetimes",
    year         = "1990",
    pages        = "329-340",
    journal      = "Quality and Reliability Engineering International",
    volume       = "6",
    editor       = "",
    number       = "",
    publisher    = "",
    url          = "http://www2.compute.dtu.dk/pubdb/pubs/2571-full.html"
}