La. Stat. tit. 39 § 509
Every ordinance or resolution authorizing the issuance of bonds under this Part shall be published at least once in the official journal of the governmental entity issuing the bonds, or in a newspaper having general circulation therein. Exhibits to any such ordinance or resolution need not be published if the exhibits are enumerated in the publication and it is stated in the publication that such exhibits are available for public inspection at the office of the governing authority during regular business hours. For thirty days after the date of publication, any person in interest may contest the legality of the ordinance or resolution and of any provision therein made for the security and payment of the bonds. After that time, no one shall have any cause of action to test the regularity, formality, legality, or effectiveness of the ordinance or resolution, and provisions thereof for any cause whatsoever. Thereafter, it shall be conclusively presumed that every legal requirement for the issuance of the bonds, including all things pertaining to the election, if any, at which the bonds were authorized, has been complied with. No court shall have authority to inquire into any of these matters after the thirty days.
La. R.S. § 39:509