If in such referendum called under the provisions of this Article two thirds or more of the farmers or producers in the area in which such referendum is conducted, eligible to participate and voting therein shall vote in the affirmative and in favor of the levying and collection of such assessment proposed in such referendum on the agricultural commodity covered thereby, then such assessment shall be  collected in the manner determined and announced by the agency conducting such referendum. (1947, c. 1018, s. 12.)