{HEAD ~ An advantage} of {TAIL ~ the present invention} is that a complete set of tracking records for a package hierarchy, such as a pallet of boxes, where each box contains a number of packages etc., can be obtained in one single trace 
{ HEAD ~ An advantage } of { TAIL ~ the present invention } is that a complete set of tracking records for a package hierarchy , such as a pallet of boxes , where each box contains a number of packages etc . , can be obtained in one single trace
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