REFERENCE_TYPE is an optional field which allows the user to classify the references into specific types.
X_REFERENCE_TYPE is a fixed lexicon with the following values:
| Saved Value | Displayed Value |
|---|---|
| 00 | Not Specified |
| 01 | Employer |
| 02 | Friend |
| 03 | Relative |
| 04 | Associate |
| 05 | Professional |
| 06 | Co-Worker |
| 07 | Supervisor |
