United Nations Educational, Scientific and Cultural Organization. Division of Free Flow of Information. (1955). Trade barriers to knowledge: A manual of regulations affecting educational, scientific and cultural materials (New and rev. ed.). UNESCO.
Chicago Style (17th ed.) CitationUnited Nations Educational, Scientific and Cultural Organization. Division of Free Flow of Information. Trade Barriers to Knowledge: A Manual of Regulations Affecting Educational, Scientific and Cultural Materials. New and rev. ed. Paris: UNESCO, 1955.
ציטוט MLAUnited Nations Educational, Scientific and Cultural Organization. Division of Free Flow of Information. Trade Barriers to Knowledge: A Manual of Regulations Affecting Educational, Scientific and Cultural Materials. New and rev. ed. UNESCO, 1955.