California Code, Military and Veterans Code - MVC § 1255

Within 30 days after the filing of the petition the county elections official shall find and certify whether the petition is signed by the requisite number of qualified registered voters of the territory proposed to be annexed and of the incorporated and unincorporated portions thereof and shall present the petition with the certificate of their findings attached thereto to the board of supervisors at its first regular meeting held 10 days from the date of certification of the petition. At the regular meeting the board shall ascertain whether the petition in all respects complies with the requirements therefor, except that the certificate shall be conclusive evidence of the sufficiency of the signatures to the petition. If the board finds that the petition complies with the requirements, it shall at the same regular meeting fix a time and place for the hearing of the petition not less than 20 days nor more than 40 days after the date of the meeting, and shall direct the clerk of the board to publish a notice once a week for three successive weeks in a newspaper circulated in the territory that is proposed to be annexed, and that the board deems most likely to give notice to the inhabitants of the territory.