A computer implemented method for determining a requested map location includes providing a database holding a plurality of map objects having {TAIL ~ respective descriptors} and {HEAD ~ loci} 
A computer implemented method for determining a requested map location includes providing a database holding a plurality of map objects having { TAIL ~ respective descriptors } and { HEAD ~ loci }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD