How do I remove a reference type

Summary: We would like to remove the "Personal" reference option for candidates when applying for a position. I found an Oracle help topic that said it was not possible to edit the delivered Reference Type options, but a UDF could be created and used. I created a UDF under Candidates, but the user defined form in the career section can't see the UDF I created as it isn't under the candidate references section (and I need the other fields from that section). Is there any way to accomplish this?

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