8.4.13 Referencing Records
Some Records may need to be referenced from other messages.
To enable this, Records may contain a Cell providing a Record identifier. The combination of MessageId
as communicated in the header Record and Record identifier Cell is globally unique.
When choosing how to populate a Record identifier Cell, implementers are strongly recommended to limit themselves to letters and digits, i.e. A-Z, a-z and 0-9.