Any such ordinance may be amended or supplemented following the procedure for adoption in section 3101 of this title. At least three copies of any ordinance, as amended or supplemented, shall be filed, as provided in section 3101 of this title, in the office of the building inspector and three copies filed in the office of the municipal clerk for use by the public. (Amended 1967, No. 295 (Adj. Sess.), § 3, eff. March 20, 1968.)