The Cooperative may not sell, lease or otherwise dispose of all or any substantial portion of its property unless such sale, lease or other disposition is authorized at a meeting of the members thereof by the affirmative vote of not less than 2/3 of all of the members of the Cooperative, and unless the notice of such proposed sale, lease or other disposition shall have been contained in the notice of the meeting; provided, however, that notwithstanding anything therein contained, the board of the Cooperative, without authorization by the members thereof, shall have full power and authority to authorize the execution and delivery of a mortgage, or mortgages or a deed or deeds of trust upon, or the pledging or encumbering of, any or all of the property, assets, rights, privileges, licenses, franchises, and permits of the Cooperative, whether acquired or to be acquired, and wherever situated as well as the revenues and income there from, all upon such terms and conditions as the board shall determine, to secure any indebtedness of the Cooperative; provided further that the board may upon the authorization of a majority of those members of the Cooperative present at a meeting of the members thereof, sell, lease, or otherwise dispose of all or a substantial portion of its property to another Cooperative or foreign corporation doing business in this state pursuant to the Act under which this Cooperative is incorporated.