(a) Each person who is a producer, as defined in this subpart, at the time of the referendum and who also was a producer during the representative period, shall be entitled to only one vote in the referendum, except that: (1) In a landlord-tenant relationship, where in each of the parties is a producer, each such producer shall be entitled to one vote in the referendum; and (2) a cooperative association of producers, bona fide engaged in marketing the commodity or product thereof proposed to be regulated, or in rendering services for or advancing the interest of the producers of such commodity or product, may, if it elects to do so, vote, both by number and total volume, for the producers who are members of, stockholders in, or under contract with such association.(b) Whenever, as required by the act, processors vote on the issuance of an order, each processor who is engaged in canning or freezing within the production area of the commodity covered by the order shall be entitled to vote in the referendum the quantity of such commodity canned or frozen within the production area for market by him during the representative period determined by the Secretary.(c) Proxy voting is not authorized but an officer or employee of a corporate producer, processor or cooperative association, or an administrator, executor or trustee of a producing estate may cast a ballot on behalf of such producer, processor, estate, or cooperative association. Any individual so voting in a referendum shall certify that he is an officer or employee of the producer, processor, or cooperative association, or an administrator, executor, or trustee of a producing estate, and that he has the authority to take such action. Upon request of the referendum agent, the individual shall submit adequate evidence of such authority.(d) Each producer, cooperative association of producers, and processor entitled to vote in a referendum shall be entitled to cast one ballot in the referendum. Each producer, cooperative association of producers, and processor casting more than one ballot with conflicting votes shall thereby invalidate all ballots cast by such producer, cooperative association of producers, or processor in such referendum.