Negative voltage at node 38 is obtained from {TAIL ~ a negative voltage} appearing at node 25 for application to {HEAD ~ gates} of pull up and pull down transistors 42 and 41, as is explained in more detail elsewhere herein 
Negative voltage at node 38 is obtained from { TAIL ~ a negative voltage } appearing at node 25 for application to { HEAD ~ gates } of pull up and pull down transistors 42 and 41 , as is explained in more detail elsewhere herein
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH