# PEPPOL-EN16931-R004-SG

Source: https://xmlvalid.com/rules/PEPPOL-EN16931-R004-SG

> Specification identifier MUST have the value 'urn:peppol:pint:billing-1@sg-1'.

- Level: error
- Rule sets: PINT SG rules (Singapore) 1.4.1
- Context: `/ubl:Invoice | /cn:CreditNote`
- Test: `starts-with(normalize-space(cbc:CustomizationID/text()), 'urn:peppol:pint:billing-1@sg-1')`

Validate a document against these rules: https://xmlvalid.com/validate