(2) It shall also have the right to cite witnesses or persons under investigation for contempt for refusal to testify before it or before any of its committees or to produce papers, documents or things required by the assembly or any of its concerned committees; (3) The rights of persons appearing in or affected by such inquiries shall be respected; (4) The Regional Assembly may, in aid of legislation require the presence of the regional cabinet members or their deputies and other officials as its rules shall provide, for questioning on matters falling within the scope of their powers and functions; and (5) The Regional Assembly may require any regional commission, office, or agency of the national government with offices in the autonomous region to explain matters relating to the exercise of its powers and functions. SEC. 7. Power to Propose Amendments to the Organic Act. - The Organic Act may be amended or revised by the Congress of the Philippines upon a vote of two thirds (2/3) of the Members of the House of Representatives and of the Senate voting separately. (1) The Regional Assembly may initiate proposals for amendment to or revisions of the Organic Act by a vote of three-fourths (3/4) of all its Members; and (2) It may also in like manner call for a Regional Consultative Commission to propose the amendment or revision. SEC. 8. Validity of Amendments to the Organic Act. - Any amendment to or revision of the Organic Act shall become effective only when approved by majority of the votes cast in the plebiscite called for the purpose, which shall be held not earlier than sixty (60) days or later than ninety (90) days after the approval of such amendment or revision. SEC. 9. Expansion of the Area of Autonomy. – The Regional Assembly shall have the power to initiate proposals for the enactment of a law that shall provide that cluster of contiguous-Muslim-dominated municipalities voting in favor of autonomy be merged and constituted into a new province(s) which shall become part of the Autonomous Region, upon approval by Congress of the Philippines, in accordance with Section 1, Article 2 of Republic Act 9054. 12