Audit by tax authorities: prescribed notice, record access and findings can trigger enforcement action. Authorises tax authorities to audit taxable persons at business premises or offices with prescribed procedures and prior notice; defines commencement of audit and allows a single written extension by the Commissioner. Authorised officers may verify records, require information and assistance; upon conclusion the proper officer must notify findings, reasons and taxpayer rights. Detection of unpaid or short-paid tax, erroneous refunds, or wrongly availed input tax credit may lead to initiation of assessment or other enforcement action.