# DT-CIUS-PT-007

Source: https://xmlvalid.com/rules/DT-CIUS-PT-007

> The BT-8 only allows the following values: 3, 35, 432.

- Level: error
- Rule sets: CIUS-PT rules (Portugal, UBL) 2.1.1
- Context: `//ubl:Invoice/cac:InvoicePeriod/cbc:DescriptionCode | //cn:CreditNote/cac:InvoicePeriod/cbc:DescriptionCode`
- Test: `(matches(.,'^(\d{1,3})$') and contains('3,35,432,', concat(normalize-space(.), ',')))`

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