A method 1, wherein {HEAD ~ the length} of the fiber ends released by the action of {TAIL ~ said external force} is at least 3 mm 
A method 1 , wherein { HEAD ~ the length } of the fiber ends released by the action of { TAIL ~ said external force } is at least 3 mm
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH