# aligned-ibrp-052

Source: https://xmlvalid.com/rules/aligned-ibrp-052

> An Invoice MUST have an invoice period (ibg-14) or an Invoice line period (ibg-26).

- Level: error
- Rule sets: PINT JP rules (Japan) 1.1.3
- Context: `/ubl:Invoice | /cn:CreditNote`
- Test: `exists(//cac:InvoicePeriod)`

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