@preamble{ "\newcommand{\noopsort}[1]{} "
        # "\newcommand{\printfirst}[2]{#1} "
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@string{rrw="R.R. Weber"}
@string{gw="G. Weiss"}
@string{kg="Glazebrook, K.D."}
@string{aap="Adv. Appl. Prob."}
@string{jap="J. Appl. Prob."}
@string{mor="Mathematics of Operations Research"}
@string{ms="Management Science"}
@string{om="Omega"}
@string{or="Operations Research"}
@string{naval="Naval Research Logistics Quarterly"}
@string{peis="Probability in the Engineering and Informational Sciences"}
@string{auto="IEEE Trans. Auto. Control"}

@article{Bel80,
   author    = {Bell, C.E.},
   title     = {Optimal Operation of a {$M/M/2$} Queue with Removable Servers},
   journal   = or,
   year      = 1980,
   volume    = {{\bf 28}},
   pages     = {1189--1204}
}


@article{Eph80,
   author    = {Ephrimedes, A. and Varaiya, P. and Walrand, J.},
   title     = {A Simple Dynamic Routing Problem},
   journal   = auto,
   year      = 1980,
   volume    = {{\bf 25}},
   pages     = {690--693}
}


@article{Haj84,
   author    = {Hajek, B.},
   title     = {Optimal Control of Two Interacting Service Stations},
   journal   = auto,
   year      = 1984,
   volume    = {{\bf 29}},
   pages     = {491--499}
}


@article{Hor90,
   author    = {Hordijk, A. and Koole, G.},
   title     = {On the Optimality of the Generalized Shortest Queue Policy},
   journal   = peis,
   year      = 1990,
   volume    = {{\bf 4}},
   pages     = {477--487}
}


@article{Ros89a,
   author    = {Rosberg, Z. and Kermani, P.},
   title     = {Customer Routing to Different Servers with Complete Information},
   journal   = aap,
   year      = 1989,
   volume    = {{\bf 21}},
   pages     = {861--882}
}


@article{Sob82,
   author    = {Sobel, M.},
   title     = {The Optimality of Full-Service Policies},
   journal   = or,
   year      = 1982,
   volume    = {{\bf 30}},
   pages     = {619--635}
}


@article{Sti85,
   author    = {Stidham, S.},
   title     = {Optimal Control of Admission to a Queueing System},
   journal   = auto,
   year      = 1985,
   volume    = {{\bf 30}},
   pages     = {705--713}
}


@article{Web78,
   author    = rrw,
   title     = {On the optimal assignment of customers to parallel servers},
   journal   = jap,
   year      = 1978,
   volume    = {{\bf 15}},
   pages     = {406--413}
}


@article{Whi86,
   author    = {Whitt, W.},
   title     = {Deciding which Queue to Join: Some Counterexamples},
   journal   = or,
   year      = 1986,
   volume    = {{\bf 34}},
   pages     = {55--62}
}


@article{Win77,
   author    = {Winston, W.},
   title     = {Optimality of the Shortest Line Discipline},
   journal   = jap,
   year      = 1977,
   volume    = {{\bf 14}},
   pages     = {181--189}
}


@article{Win77a,
   author    = {Winston, W.},
   title     = {Assignment of Customers to Servers in a Heterogeneous 
                Queueing System with Switching},
   journal   = or,
   year      = 1977,
   volume    = {{\bf 25}},
   pages     = {469--483}
}


@article{Xu91d,
   author    = {Xu, S.H.},
   title     = {Socially and individually optimal routing of stochastic jobs on
                parallel processor systems},
   journal   = or,
   year      = 1991,
   volume    = {{\bf 38}},
   pages     = {387--375}
}