All papers comprising a petition for initiative or referendum shall be assembled and filed with the City Secretary as one instrument. Within thirty (30) days after the petition is filed, the City Secretary shall determine whether each paper of the petition has a proper statement of the circulator and whether the petition has been signed by a sufficient number of qualified electors and shall hold any petition paper entirely invalid which does not have attached thereto the statement signed by the circulator thereof. The City Secretary shall certify the result of this examination to the Council at its next regular meeting. If the City Secretary shall certify that the petition is insufficient, the certificate shall specify the particulars in which it is defective and shall at once notify in writing the person filing the petition of this finding. A petition may be amended at anytime within ten (10) days after a notice of insufficiency has been sent by the City Secretary, by filing a supplementary petition. In such event, the same procedures shall then be followed by the City Secretary and Council as in the case of the original petition for the same purpose.