[aligned-ibrp-009]-Seller tax identifier (ibt-031) MUST occur maximum once.
aligned-ibrp-009
/ubl:Invoice | /cn:CreditNote
(count(cac:AccountingSupplierParty/cac:Party/cac:PartyTaxScheme[cac:TaxScheme/upper-case(cbc:ID)='VAT']/cbc:CompanyID) <= 1)