Preemptive scheduling in a two-stage multiprocessor flow shop is NP-hard

Arthanari, 1974, On some problems of sequencing and grouping Blazewicz, 1992 Brah, 1991, Branch and bound algorithm for the flow shop with multiple processors, European Journal of Operational Research, 51, 88, 10.1016/0377-2217(91)90148-O Buten, 1973, A scheduling model for computer systems with two classes of processors, 130 Graham, 1979, Optimization and approximation in deterministic sequencing and scheduling: A survey, Ann. Discrete Mathematics, 5, 287, 10.1016/S0167-5060(08)70356-X Johnson, 1954, Optimal two- and three-stage production schedules with set-up times included, Naval Research Logistics Quarterly, 1, 61, 10.1002/nav.3800010110 McNaughton, 1959, Scheduling with deadlines and loss functions, Management Science, 6, 1, 10.1287/mnsc.6.1.1 Sriskandarajah, 1989, Scheduling algorithms for flexible flowshops: Worst and average case performance, European Journal of Operational Research, 43, 143, 10.1016/0377-2217(89)90208-7 Vandevelde, 1995