Invoice Reference Number requirement mandates electronic uploading with FORM GST INV-01; noncompliant documents will not be treated as invoices. The amendment adds sub rules to rule 48 requiring that notified classes of registered persons prepare invoices by including particulars in FORM GST INV-01 and obtain an Invoice Reference Number by uploading that information on the Common Goods and Services Tax Electronic Portal under conditions set by notification; invoices issued otherwise by such persons will not be treated as invoices, and sub rules (1) and (2) of rule 48 do not apply to invoices prepared under this electronic procedure.