{HEAD ~ The respective outputs} of the filters are coupled through {TAIL ~ a multiplexer} to a squarer 
are coupled through
{ HEAD ~ The respective outputs } of the filters are coupled through { TAIL ~ a multiplexer } to a squarer
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH