Metal alloys for the reflective or {HEAD ~ the semi reflective layer} of {TAIL ~ an optical storage medium} 
of
Metal alloys for the reflective or { HEAD ~ the semi reflective layer } of { TAIL ~ an optical storage medium }
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL