{TAIL ~ Neither the first input signal} nor the second input signal are applied to a base or gate of {HEAD ~ the fourth transistor} 
{ TAIL ~ Neither the first input signal } nor the second input signal are applied to a base or gate of { HEAD ~ the fourth transistor }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD