Electronic Reference Number for GST invoices required; application form lists mandatory invoice, consignee and tax particulars. Application form for issuance of an Electronic Reference Number for a GST invoice requiring supplier GSTIN, name and address, invoice serial and date, consignee and receiver details with state and GSTIN/unique ID, item-level particulars (description, quantity, unit, discounts, taxable value), CGST/SGST/IGST rates and amounts, ancillary charges, total invoice value, tax subject to reverse charge, declaration, signatory name/designation/signature, and space for the Electronic Reference Number and date.