All posting in the libraries is permitted only on the regularly designated bulletin boards, and must be approved by the library. Responsibility and supervision of all bulletin boards in the library is assigned to the reference department. All posters or materials requested to be displayed by students are expected to carry the associated students' stamp and to be dated. Posters that do not carry the associated students' stamp or that are requested to be displayed by faculty or nonstudent groups may be approved in the discretion of the director of libraries or his or her designee.