{HEAD ~ Header file} 900 is {TAIL ~ an example} of an implementation of header file 304 in FIG 3 
is
{ HEAD ~ Header file } 900 is { TAIL ~ an example } of an implementation of header file 304 in FIG 3
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH