The method 60, wherein {HEAD ~ the region} is identified with sufficient precision to distinguish {TAIL ~ the region} from 1.5×1014 other regions 
The method 60 , wherein { HEAD ~ the region } is identified with sufficient precision to distinguish { TAIL ~ the region } from 1.5×1014 other regions
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