{HEAD ~ These operations} include identifying a source data structure and a source attribute associated with the source data structure and identifying {TAIL ~ a destination data structure} and a destination attribute associated with the destination data structure 
{ HEAD ~ These operations } include identifying a source data structure and a source attribute associated with the source data structure and identifying { TAIL ~ a destination data structure } and a destination attribute associated with the destination data structure
HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH