# UBL-FREXT-SR-48

Source: https://xmlvalid.com/rules/UBL-FREXT-SR-48

> Invoice lines shall have one and only one classified tax category, if no subtype and subtype = "DETAIL", else no more than 1.

- Level: error
- Rule sets: EXTENDED-CTC-FR rules (UBL) 1.4.0.04
- Context: `cac:InvoiceLine | cac:CreditNoteLine`
- Test: `($lineInCalul and (count(cac:Item/cac:ClassifiedTaxCategory) = 1)) or (not($lineInCalul) and (count(cac:Item/cac:ClassifiedTaxCategory) le 1))`

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