J. Artalejo, D. S. Orlovsky, and A. N. Dudin, Multiserver retrial model with variable number of active servers, Computers and Industrial Engineering, vol.28, pp.273-288, 2005.

S. Asmussen, O. Nerman, and M. Olsson, Fitting Phase-Type Distributions via the EM Algorithm, Scandinavian Journal of Statistics, vol.23, pp.419-441, 1996.

J. E. Diamond and A. S. Alfa, On approximating higher order M AP s with M AP s of order two, Queueing Systems, vol.34, issue.1/4, pp.269-288, 2000.
DOI : 10.1023/A:1019165221472

A. Dudin, Optimal multi-threshold control for a BM AP/G/1 queue with N service modes, Queueing Systems, vol.30, issue.3/4, pp.273-287, 1998.
DOI : 10.1023/A:1019121222439

A. N. Dudin and V. I. Klimenok, Optimal admission control in a queueing system with heterogeneous traffic, Operations Research Letters, vol.31, issue.2, pp.108-118, 2003.
DOI : 10.1016/S0167-6377(02)00218-3

A. Graham, Kronecker Products and Matrix Calculus with Applications, 1981.

C. S. Kim, V. I. Klimenok, A. A. Birukov, and A. N. Dudin, Optimal multi-threshold control by the BMAP/SM/1 retrial system, Annals of Operations Research, vol.7, issue.1, pp.193-210, 2006.
DOI : 10.1007/s10479-006-5299-3

V. I. Klimenok, C. S. Kim, D. S. Orlovsky, and A. N. Dudin, Lack of Invariant Property of the Erlang Loss Model in Case of MAP Input, Queueing Systems, vol.7, issue.2, pp.187-213, 2005.
DOI : 10.1007/s11134-005-6481-z

D. M. Lucantoni, New results on the single server queue with a batch markovian arrival process, Communications in Statistics. Stochastic Models, vol.21, issue.1, pp.1-46, 1991.
DOI : 10.1080/15326348508807003

M. Neuts, Matrix-Geometric Solutions to Stochastic Models, 1981.
DOI : 10.1007/978-3-642-69546-9_91

A. Pattavina, A. Parini, and A. , Modelling voice call inter-arrival and holding time distributions in mobile networks, Performance Challenges for Efficient Next Generation Networks -Proc.of 19th International Teletraffic Congress, pp.729-738, 2005.

J. Talim, Z. Liu, P. Nain, E. G. Coffman, and J. , Controlling the robots of Web search engines, ACM SIGMETRICS Performance Evaluation Review, vol.29, issue.1, pp.236-244, 2001.
DOI : 10.1145/384268.378788

H. Tijms, On the optimality of a swith-over policy for controlling the queue size in a M/G/1 queue with variable service rates, Lecture Notes in Computer Sciences, vol.40, pp.236-242, 1976.

C. E. Wells, Determining the Future Costs of Lifetime Warranties, IIE Transactions, vol.19, issue.2, pp.178-181, 1987.
DOI : 10.1109/TR.1983.5221650