It will be appreciated that {HEAD ~ the term sheet} is used herein in a broad sense and is not limited to planar shapes or to shapes not exceeding a certain thickness or to {TAIL ~ shapes} of constant thickness 
is not limited to
It will be appreciated that { HEAD ~ the term sheet } is used herein in a broad sense and is not limited to planar shapes or to shapes not exceeding a certain thickness or to { TAIL ~ shapes } of constant thickness
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH