Without prejudice to any special provisions having effect by virtue of this Part of this Act, the Commission may from time to time serve on any person registered in the Commission's register, or on the board administering any marketing scheme, or on the authorised body constituted under a co-operative scheme, a written notice requiring that person, board or body to furnish to the Commission such returns and other information specified in the notice as the Commission may require for the discharge of its functions under this Part of this Act or any scheme or regulations having effect by virtue of this Part of this Act.