As discussed earlier, {HEAD ~ the glass sheet} 10 must also be heated to relieve any internal stresses resulting from {TAIL ~ the concentrated heat} and prevent thermal fracturing of the glass 
As discussed earlier , { HEAD ~ the glass sheet } 10 must also be heated to relieve any internal stresses resulting from { TAIL ~ the concentrated heat } and prevent thermal fracturing of the glass
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH