# BR-FR-06_BT-21_TXD

Source: https://xmlvalid.com/rules/BR-FR-06_BT-21_TXD

> BR-FR-06/BT-21 : Le code sujet TXD (mention de taxe) ne doit apparaître qu'une seule fois dans les notes (BG-1).

- Level: error
- Rule sets: French e-invoicing rules (CII) 1.4.0.04
- Context: `rsm:CrossIndustryInvoice/rsm:ExchangedDocument`
- Test: `count($notes[ram:SubjectCode = 'TXD']) le 1`

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