{HEAD ~ A system} 2, wherein {TAIL ~ the one or more directives} comprise an inbound and an outbound directive 
{ HEAD ~ A system } 2 , wherein { TAIL ~ the one or more directives } comprise an inbound and an outbound directive
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH