1. The sale of the electric generating plant of the city, the electric distribution system to the entire electric utility, or of the water utility, shall be made only by authority of a special non-emergency ordinance. Such ordinance shall be published in full in a newspaper of general circulation within the city within ten days after its passage, and shall not become effective until it shall have been referred to the qualified electors of the city at a general or special election and approved by a majority of the qualified electors voting on the question of approving the ordinance; and
2. The sale of any other property, real, personal or mixed, or of any interest therein, the value of which is more than $10,000, shall be made only by authority of a special non-emergency ordinance. Such ordinance shall be published in full passage, and shall include a section reading substantially as follows: Section--. This ordinance shall be referred to a vote of the electors of the city if a proper referendum petition is properly filed within thirty days after its passage; otherwise it shall go into effect thirty days after its passage.