Optionally, {HEAD ~ only a portion} of {TAIL ~ the sought digital content} is downloaded using single source download, establishing that such a portion of the sought content is made available by the distributor 
of
Optionally , { HEAD ~ only a portion } of { TAIL ~ the sought digital content } is downloaded using single source download , establishing that such a portion of the sought content is made available by the distributor
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH