R.I. Gen. Laws § 7-1.2-706: Greater voting requirements.

Whenever, with respect to any action to be taken by the shareholders of a corporation, the articles of incorporation require the vote of the holders of a greater proportion of the shares, or of any class or series of the shares, than required by this chapter with respect to the action, the provisions of the articles of incorporation control. An amendment of the articles of incorporation which changes or deletes a provision is authorized by the same vote as would be required to take action under the provision.