@article{RO_2007__41_4_399_0,
     author = {Ouhbi, Brahim and Boudi, Ali and Tkiouat, Mohamed},
     title = {The expected cumulative operational time for finite {semi-Markov} systems and estimation},
     journal = {RAIRO - Operations Research - Recherche Op\'erationnelle},
     pages = {399--410},
     publisher = {EDP-Sciences},
     volume = {41},
     number = {4},
     year = {2007},
     doi = {10.1051/ro:2007029},
     mrnumber = {2361293},
     language = {en},
     url = {http://www.numdam.org/articles/10.1051/ro:2007029/}
}