Wherever in this title petitions are required to be signed by the owners of property, the following rules shall govern the sufficiency of the petitions:
(1) The signature of a record owner, as determined by the records of the county auditor of the county in which the real property is located, shall be sufficient without the signature of the owner's spouse.
(2) For mortgaged property, the signature of the mortgagor shall be sufficient.
(3) For property purchased on contract, the signature of the contract purchaser, as shown by the records of the county auditor of the county in which the real property is located, shall be sufficient.
(4) Any officer of a corporation owning land in the district duly authorized to execute deeds or encumbrances on behalf of the corporation may sign on behalf of that corporation, except that there shall be attached to the petition a certified excerpt from the bylaws showing such authority.
(5) If any property in the district stands in the name of a deceased person or any person for whom a guardian has been appointed, the signature of the personal representative, administrator, or guardian, as the case may be, shall be equivalent to the signature of the owner of the property.