{TAIL ~ The chosen model approach} contains {HEAD ~ modeling} of an external exhaust gas recycling system, variable inlet systems and systems with variable control valves 
{ TAIL ~ The chosen model approach } contains { HEAD ~ modeling } of an external exhaust gas recycling system , variable inlet systems and systems with variable control valves
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH