# BR-52

Source: https://xmlvalid.com/rules/BR-52

> Each Additional supporting document (BG-24) shall contain a Supporting document reference (BT-122).

- Level: error
- Rule sets: EN 16931 rules (UBL) 1.3.17, EN 16931 rules 1.3.16 (UBL), EXTENDED-CTC-FR rules (UBL) 1.4.0.04
- Context: `cac:AdditionalDocumentReference`
- Test: `normalize-space(cbc:ID) != ''`

> Each Additional supporting document (BG-24) shall contain a Supporting document reference (BT-122).

- Level: error
- Rule sets: EN 16931 rules (CII) 1.3.17, EN 16931 rules 1.3.16 (CII), EXTENDED-CTC-FR rules (CII) 1.4.0.04
- Context: `//ram:AdditionalReferencedDocument`
- Test: `normalize-space(ram:IssuerAssignedID) != ''`

> Each Additional supporting document (BG-24) shall contain a Supporting document reference (BT-122).

- Level: error
- Rule sets: Romanian RO e-Factura rules (UBL) 1.0.9
- Context: `cac:AdditionalDocumentReference`
- Test: `(cbc:ID) != ''`

> Each Additional supporting document (BG-24) shall contain a Supporting document reference (BT-122).

- Level: error
- Rule sets: Factur-X EN 16931 rules 1.09.2, Factur-X EXTENDED rules 1.09.2
- Context: `//ram:AdditionalReferencedDocument`
- Test: `(ram:IssuerAssignedID!='')`

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