A monitor unit which can monitor {HEAD ~ equivalent operation} of the processing sets can also include {TAIL ~ the mutex ordering mechanism} 
A monitor unit which can monitor { HEAD ~ equivalent operation } of the processing sets can also include { TAIL ~ the mutex ordering mechanism }
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL