Before making a sale of any of the bonds, notice shall be given by publication once a week, for two weeks, in a newspaper of general circulation in the district, if there is one, and no sale shall be held prior to the expiration of 15 days from the first publication of the notice. Copies of such advertisement may be published in any newspaper or financial publication in the United States and copies may be mailed to recognized investment dealers, banks, investing institutions and statistical organizations, together with any related material pertaining to the district and its bonds, but no defect in any such additional publication or failure to mail or failure of any
person to receive copies of any such materials so mailed shall affect the validity of the sale. The board may reject any or all bids received if it determines that the bids are not satisfactory as to price or as to the responsibility of the bidders. If no bids are received or if the board rejects all bids received, the board may either readvertise or sell the bonds at private sale, provided, however, that if the bonds are sold at private sale, they shall not be sold at a price lower than the highest bid, if any, which was received at the public sale.