{HEAD ~ The end conductive segments} at {TAIL ~ each polygon vertex} in at least one inner row are joined in the inner row 
at
{ HEAD ~ The end conductive segments } at { TAIL ~ each polygon vertex } in at least one inner row are joined in the inner row
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH