At any time after any such book shall have been so delivered to the register or clerk as provided in § 30-13-10, the association which has delivered it may request the register or clerk to whom such book has been delivered to record therein any marketing contracts or agreements which have been entered into by such association and any members thereof. But if any such contracts or agreements be in the same words and figures as any other contracts or agreements with any other members of the association, with or without notations at the end thereof, and be separately signed by such members of the association, such association may have any such contract or agreement recorded once in extenso in such book and may furnish the register or the clerk with a list of the names of persons appearing on such contracts as signers thereof, with the dates, if any, of the signatures, respectively, together with a statement of any such notations, whereupon the register or clerk shall record such names as signatures, respectively, and the notations, if any, so furnished. Such recordation of the list of signatures so furnished shall be equivalent to the recordation in extenso of the contract or agreement of each signer thereof. Such copy of such contracts or agreements and such list of names of persons appearing on such contracts as signers thereof and statement of notations shall be sworn to by some officer of the association cognizant of the facts before some officer authorized to take acknowledgments to deeds. But in no case shall any such contract or agreement be deemed to be recorded as to any signer thereof until his name shall be indexed in such book by the register or clerk, which indexing such officer is hereby required to do.