A tree structure resembling the packaging hierarchy is disclosed, where {HEAD ~ the nodes} are referenced by {TAIL ~ the unique reference}, and tracing of entire sub trees may be performed by entering a unique code 
A tree structure resembling the packaging hierarchy is disclosed , where { HEAD ~ the nodes } are referenced by { TAIL ~ the unique reference } , and tracing of entire sub trees may be performed by entering a unique code
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH