[ibr-174-ae]-In Item Information (IBG-31) where Invoiced VAT category code (IBT-151) is 'Reverse charge', the corresponding Item Standard Identifier (IBT-157) MUST be there and the Scheme Identifier (IBT-157-1) should have the code 0160.
ibr-174-aecac:InvoiceLine/cac:Item/cac:ClassifiedTaxCategory[normalize-space(cbc:ID) = 'AE'][cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT'] | cac:CreditNoteLine/cac:Item/cac:ClassifiedTaxCategory[normalize-space(cbc:ID) = 'AE'][cac:TaxScheme/normalize-space(upper-case(cbc:ID))='VAT']not(not(exists(../cac:StandardItemIdentification/cbc:ID)) or ../cac:StandardItemIdentification/cbc:ID/@schemeID != "0160")