Within ten days from the filing of any initiative or referendum petition, the city clerk shall ascertain whether the petition is signed by the requisite number of registered electors, and if sufficient shall attach thereto his certificate of sufficiency showing the result of such examination. If the petition be insufficient, he shall forthwith in writing notify one or more of the persons designated on the petition as filing the same. The petition may then be amended within ten days from the filing of the certificate. The city clerk, within five days after such amendment, shall make like examination of the amended petition and attach thereto his certificate of the result. If still insufficient, he shall return the petition to one of the persons designated therein as filing it, without prejudice to the filing of a new petition for the same purpose, but such petition shall not be refiled within one year after return by the clerk. (Ord. No. 91-47, § 1, 11-13-1991)