The legislative body shall provide for the issuance of the refunding bonds.

In no event shall refunding bonds be issued for more than the par value of the outstanding bonds and the due and unpaid interest coupons to be refunded.

The refunding bonds shall represent and be secured by said reassessments and any later reassessments which may be levied or issued upon the same property in lieu of said assessments.

Refunding bonds issued pursuant to this division shall comply with the following requirements:

clerk, the seal of the city affixed thereto.

All of the refunding bonds shall mature on July 2d.

In no event shall the first maturity of any refunding bonds be earlier than the second day of July next succeeding 10 months after the date of the bonds.

The last maturity of any refunding bonds shall not exceed 19 years from the second day of July next succeeding 10 months after the date of said bonds.

The rate of interest on refunding bonds shall not exceed the rate of interest on the outstanding bonds.

The interest on refunding bonds shall be payable on January 2d and July 2d, respectively, of each year.

The first interest payment on such bonds shall in every case be January 2d next preceding the second day of July next succeeding 10 months after the date of the bonds.

Refunding bonds and the interest thereon shall be paid at the office of the treasurer.

Refunding bonds may be issued in substantially the following form:

Each bond shall be conclusive evidence of the regularity of all proceedings for the issuance of refunding bonds and of the validity of said bonds and of all proceedings of which the bonds refunded were conclusive evidence.

The refunding bonds shall be delivered to the holders of the outstanding bonds in accordance with the contract with such bondholders.

When the refunding bonds have been exchanged for the outstanding bonds, the outstanding bonds, except as to any sum payable from assessments which property owners have by written notice elected to pay, shall be canceled by the city treasurer and shall be filed in the office of the treasurer.

If the city has appropriated money to assist in the refunding, such money shall be paid to the holders of outstanding bonds in accordance with the contract with the bondholders.

The validity of any refunding bonds issued under this division shall not be contested in any action, suit or proceeding unless such action or proceeding shall have been brought within three months after the issuance of such bonds.

The treasurer shall keep a register in his office which shall show the series, number, date, amount, rate of interest, and last known holder of each bond and the number and amount of each interest coupon paid by him. He shall cancel and file each bond and coupon paid.