Well I want to refer to things that are widely standardized within countries: Business registration numbers and bank account numbers. However when you go inter

Well I want to refer to things that are widely standardized within countries: Business registration numbers and bank account numbers. However when you go international, how should you refer to "business registration number in Norway"? Perhaps you encode that as "NO" but then you hit Denmark which has not 1 but 5 business registries.... The ONLY thing missing is really a standard way to refer to "the registry in which the ID is registered". Like "urn:isbn:" does. I would love to have the same e.g. for referring to a business registration number or bank account number. Making my own URLs to refer to a business registration number that users of the system provides...not sure in what way I would do that or what value it would give.