Optimal threshold policies in a workload model with a variable number of service phases per job. - Gido A. J. F. Brouns; Jan van der Wal (Math. Methods Oper. Res., 2003)

Optimal threshold policies in a two-class preemptive priority queue with admission and termination control. - Gido A. J. F. Brouns; Jan van der Wal (Queueing Syst. Theory Appl., 2006)