[Pledge of fees levied.]

The issuance and sale of such debentures shall constitute and be an irrevocable and irrepealable contract between the state of New Mexico and the owner of any said debentures, that the taxes or fees pledged for the payment thereof at the rate now provided by this act shall not be reduced as long as any of said debentures remain outstanding, and unpaid, and that the state will cause said taxes and fees to be promptly collected, remitted and set aside and applied to pay said debentures, and the interest thereon according to the terms thereof. Any holder of any of the debentures issued pursuant to the provisions of this act, or any person or officer being a party in interest may, either at law or in equity, by suit, action or mandamus, enforce and compel the performance of the duties required by this act of any officer or person herein mentioned.