7. Every member of the Institute in practice shall, and any other member may, use the designation of a Chartered Accountant and no member using such designation shall use any other designation, whether in addition thereto or in substitution therefore: Provided that nothing contained in this section shall be deemed to prohibit any such person from adding any other description or designatory letters to his name, if entitled thereto, to indicate membership of such other institute of accountancy, whether in Bangladesh or elsewhere as may be recognised in this behalf by the Council, or any other qualification that he may possess, or to prohibit a firm, all the partners of which are members of the Institute and in practice, from being known by its firm name as Chartered Accountants.