In the event bonds issued hereunder are not secured by a trust indenture as provided for in section fifteen of this article, there shall be, and there is hereby, created a statutory mortgage lien upon such athletic establishment acquired or constructed under the provisions of this article, which shall exist in favor of the holder of said bonds, and each of them, and to and in favor of the holder of the coupons attached to said bonds, and such athletic establishment shall remain subject to such statutory mortgage lien until payment in full of the principal and interest of said bonds. Any holder of bonds issued under the provisions of this article, or of any coupons representing interest accrued thereon, may, either at law or in equity, enforce the statutory mortgage lien hereby conferred and may, by proper suit, compel the performance of the duties of the board set forth in this article.