Upon the filing of such petition for an order of dissolution, the superior court shall enter an order setting the same for hearing at a date not less than thirty days from the date of filing, and the petitioner shall give notice of such hearing by publication in a newspaper of general circulation in the county in which the district is located once a week for three successive weeks, and by posting in three public places in the county in which the district is located at least twenty-one days before said hearing. At least one notice shall be posted in the district. The notices shall set forth the filing of the petition, its purpose and the date and place of the hearing thereon.