Another aspect of the present invention comprises locating {HEAD ~ the symbol} by identifying {TAIL ~ at least a portion} of the data cell border 
by identifying
Another aspect of the present invention comprises locating { HEAD ~ the symbol } by identifying { TAIL ~ at least a portion } of the data cell border
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH