The board of directors by resolution entered on its minutes shall prescribe the form of the bonds and of the interest coupons attached thereto, shall fix the time when the whole or any part of the principal of said bonds shall be payable, which shall not be more than 30 years after their date of issuance, the denomination or denominations of the bonds, the date or dates of issuance of such bonds, the number or numbers of the bonds maturing at each date of maturity and the place or places of payment of such bonds. Said bonds may be payable at the office of the district or at the office of the county treasurer of the organizing county, or at any place or places designated therein at holder’s option.