California Code, Elections Code - ELEC § 10221

(a) Except as provided in subdivision (b), the signatures to each nomination paper shall be appended on the same sheet of paper, and each signer shall add his or her place of residence, giving the street and number, if any, or another designation of his or her place of residence, so as to enable its location to be readily ascertained.

(b) Once a nomination paper is filed with the elections official, the nomination paper may not be returned to the candidate to obtain additional signatures.  If the nomination paper is determined to be insufficient or the candidate fails to obtain the correct number of valid signatures on his or her nomination paper, the elections official shall retain the original nomination paper, provide a copy of the nomination paper to the candidate with an indication on of which signatures are valid, and issue one supplemental petition to the candidate on which the candidate may collect additional signatures.  The supplemental petition shall be filed not later than the last day for filing for that office.  The form of the supplemental petition shall be the same as the nomination paper, except that the word “Supplemental” shall be inserted above the phrase “Nomination Paper.”