Mexico

type Invoice {
  // ...all generic invoice fieldse
  lines: [
    // ...everything from invoice.lines
    itemCode: string;
    unit: UnitsOfMeasure;
    vat: {
      // ...everything from invoice.lines.vat
      category: string;
      typeCode: string;
      factorCode: string;
    }
  ],
  customInfo: {
    mex: {
      typeCode: string;
      recipientTaxIdType: string;
      recipientIndustryClassificationCode: string;
      paymentMeansCode: string;
      paymentChannelCode: string;
    }
  }
}