[BR-CO-20]-If Invoice line period (BG-26) is used, the Invoice line period start date (BT-134) or the Invoice line period end date (BT-135) shall be filled, or both.
BR-CO-20pxs-taxdata:TaxData/pxs-taxdata:ReportedTransaction/pxs-taxdata:ReportedDocument/pxs-taxdata:DocumentLine/cac:InvoicePeriodexists(cbc:StartDate) or exists(cbc:EndDate)