The article 1 is produced by means of {TAIL ~ a mould} 10 whose moulding surface 11 has {HEAD ~ a shape} matching the shape of the convex surface 4 of the required article 1 
The article 1 is produced by means of { TAIL ~ a mould } 10 whose moulding surface 11 has { HEAD ~ a shape } matching the shape of the convex surface 4 of the required article 1
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH