How in a mail retrieve the text and not the code of a field type list?

Hello, in the form I have a field type List and in the mail sent to next approver when I use the instruction <> WF_PROCESS_INST_RELDATA_VALUE.DEMANDE_NATURE_DEMANDE> I retrieve the code (LP) of the choosen value for the field NATURE_DEMANDE in the section DEMANDE. I want to retrieve the text (Price List) associate to this code, and not the code itself. How to do it?
Thank