Pub. L. 86-682, tit. 39, pt. IV, ch. 57, sec. 4160
Executive Departments to supply information
§ 4160. Executive Departments to supply information Persons and governmental organizations authorized to use penalty mail shall supply all information requested by the Postmaster General necessary to carry out the provisions of sections 4151–4168 of this title as soon as practicable after request therefor.