(a) Each producer shall be entitled to only one vote and to cast one ballot in each referendum; and no person who may claim to be a producer shall be refused a ballot. Each producer casting more than one ballot with conflicting votes shall thereby invalidate all ballots cast by such producer in such referendum. Each ballot cast shall contain a certification by the person casting the ballot that he is a producer.

(b) Except as provided in section 8c(5)(B) of the act, as amended, any cooperative association eligible under § 900.302 may, if it elects to do so, vote and cast one ballot for producers who are members of, stockholders in, or under contract with, such cooperative association. A cooperative association shall submit, with its ballot, a certified copy of the resolution authorizing the casting of the ballot. Each such cooperative association entitled to vote in a referendum casting more than one ballot with conflicting votes shall thereby invalidate all ballots cast by such voter in such referendum.

(c) Voting by proxy or agent, or in any manner, except by the producer or cooperative association will not be permitted; however, a producer which is other than an individual may cast its ballot by a person who is duly authorized and such ballot shall contain a certification by such person that the person on whose behalf the ballot is cast is a producer.