The secretary shall give notice of the time and place of the hearing by causing a notice thereof to be published for the time provided by Section 31371 in a newspaper of general circulation printed and published within the proposed improvement district, but if there is no such newspaper, then one within the district, but if there is no such newspaper, then one within the county in which the proposed improvement district is situated. Said publication shall be completed at least seven days prior to said hearing. The secretary shall also cause the notice to be posted in five conspicuous places within the proposed improvement district at least 10 days prior to said hearing.