(6)Every enterprise approved under sub-rule (5) shall maintain books of account and get such books audited by an accountant, as defined in Explanation to sub-section (2) of section 288 and furnish the report of such audit duly signed and verified by such accountant to the Chief Commissioner of Income-tax under whose jurisdiction it is assessed, before the due date of filing of the return under sub-section (1) of section 139.
