145A.21  Amendment of plan of merger — procedures — qualifications.
  A plan of merger once approved may be amended. An amendment shall be formulated and approved in the same manner and subject to the same limitations as provided in sections 145A.3 through 145A.9 for the formulation and approval of an original plan of merger. However, an amendment to a plan of merger shall not in any way impair the obligation of or source of payment for bonds or other indebtedness duly contracted prior to the effective date of the amendment to the plan of merger.
85 Acts, ch 123, §11