The multilateral exchange of educational audio-visual materials : existing mechanisms and suggestions for the future / Unesco. - Paris : Unesco, c 1980. - 118 p. : ill. ; 24 cm. - Educational methods and techniques ; 2 . Bibliography : p. 61-62. 300 300 ISBN: 92-3-101694-8 Subjects--Topical Terms: Audio-visual materials.Educational exchanges. Dewey Class. No.: 371.33 / U3m