Books
Pamphlets, tracts, monographs, leaflets, handbills, posters
Newspapers, magazines, quarterlies, journals, and other periodicals
Studies, special reports, periodic reports, bulletins
Minutes of meetings
Circulars, memoranda, orders, directives
Personal letters, diaries, notes, records of activities, literary attempts
Teaching and study materials
Maps, graphs, charts, drawings, pictures, films, sketches, symbolical representation
Video sound recording and electronic files