"It is certified that this bond is authorized by and is issued in conformity with the requirements of the constitution and statutes of this state."
Such recital shall be deemed to be an authorized declaration of the board and to import that there is constitutional and statutory authority for issuing the bonds and imposing the tax; that all the proceedings therefor are regular; that all acts, conditions and things required to exist, happen, and be performed precedent to and in the issuance of the bonds and imposition of the tax have existed, have happened and have been performed in due time, form, and manner as required by law; that the amount of the bonds, together with all other indebtedness of the board does not exceed any limit or limits prescribed by the constitution or statutes of this state; and that the required notices have been duly and regularly given by publication in the manner required by law. If any bonds are issued containing the above recital, the same shall be construed according to the import herein declared, and it shall be conclusively presumed that the recital is true, and neither the board nor any taxpayer shall be permitted to question the validity or regularity of the bonds, obligations or tax in any court or in any action or proceeding.
"Incontestable. Secured by a pledge and dedication of a sales and use tax in the Parish of Lafayette, Louisiana. Registered this _____ day of __________, 20___.
_____________________________
SECRETARY OF STATE"
All bonds issued under the provisions of this Section and the interest thereon shall be exempt from taxation. The bonds may be used for deposit with any officer, board, municipality, or other political subdivision of the state of Louisiana in any case where deposit of security is required.
La. Revenue and Taxation § 47:338.86