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