A method 3, wherein {HEAD ~ said step} of providing a flow of gas across {TAIL ~ said opening} is performed inside of said oven region adjacent said opening 
A method 3 , wherein { HEAD ~ said step } of providing a flow of gas across { TAIL ~ said opening } is performed inside of said oven region adjacent said opening
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH