accept first additional data received from the second data enterer into the system if the data is entered in {HEAD ~ a format} compliant with {TAIL ~ a second set} of rules 
compliant with
accept first additional data received from the second data enterer into the system if the data is entered in { HEAD ~ a format } compliant with { TAIL ~ a second set } of rules
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH