XWPR isn't a IATA / ICAO / FAA code. About Local_ref, you added personally to wiki it is not clear for what reason. You probably saw the data already marked up incorrectly or tried to systematize it this way. But local_ref it's about local reference. XWPR & similar official refs isn't a local reference. It's a national/international rank of codes. Yes, I'm having trouble understanding why after several discussions you're marking non-local refs as local (local_refs) when it's national/international. No, Wiki doesn't prohibit the use of ref, but recommends the use of IATA / ICAO / FAA (iata=*, icao=*, faa=*) codes where they mean and not use ref to specify these codes. No, except for the local (local_ref), there are also national (nat_ref), international (int_ref), regional (reg_ref). Since these codes are used both at the national and limited international level, I believe that this is just "ref" tag.