Mark Silberstein Dan Geiger Assaf Schuster Miron Livny Scheduling Mixed Workloads in Multi-grids: The Grid Execution Hierarchy. 291-302 2006 HPDC http://doi.ieeecomputersociety.org/10.1109/HPDC.2006.1652160 conf/hpdc/2006 db/conf/hpdc/hpdc2006.html#SilbersteinGSL06