{HEAD ~ The process} 52 wherein {TAIL ~ each} of the parallel processing elements generates an intermediate result for its respective partition 
wherein
{ HEAD ~ The process } 52 wherein { TAIL ~ each } of the parallel processing elements generates an intermediate result for its respective partition
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH