Mandatory
This field contains the reference number which has been assigned by the presenting bank.
This field must not start or end with a slash '/' and must not contain two consecutive slashes '//' (Error code(s): T26).
When the MT 756 is being sent to the presenting bank by the reimbursing bank, this field should contain the contents of field 20 Claiming Bank's Reference of the MT 742 Reimbursement Claim or an equivalent reference.