{HEAD ~ a second switching element} and a third switching element coupled in series between the output of the first pre buffer and {TAIL ~ the given terminal} and 
coupled between
{ HEAD ~ a second switching element } and a third switching element coupled in series between the output of the first pre buffer and { TAIL ~ the given terminal } and
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL OTH OTH REL OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH