Solicitations by salesmen, agents or peddlers, for the sale of goods or services to students, faculty or staff on any portion of the Black Hills State University campus is prohibited except as hereinafter provided:
1. Display and sale of goods and services to authorized representatives of the University for University purposes;
2. Display of instructional materials used in colleges may be permitted; and
3. Groups and individuals may appear by invitation of authorized University personnel to present proposals for group consideration.