wherein * denotes {HEAD ~ the point} of {TAIL ~ attachment} of T1 to COUP and ** denotes the point of attachment to T2  
of
wherein * denotes { HEAD ~ the point } of { TAIL ~ attachment } of T1 to COUP and * * denotes the point of attachment to T2
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH