Audio-visual techniques for industry /
Halas, John.
Audio-visual techniques for industry / prepared for the United Na tions Industrial Development Organization (UNIDO) by John Halas and Roy Martin-Harris. - New York : United Nations, 1978. - ix, 84 p. : ill. ; 30 cm. - Development and transfer of technology series ; no. 6. .
Audio-visual equipment.--------
Audio-visual materials.--------
Audio-visual techniques for industry / prepared for the United Na tions Industrial Development Organization (UNIDO) by John Halas and Roy Martin-Harris. - New York : United Nations, 1978. - ix, 84 p. : ill. ; 30 cm. - Development and transfer of technology series ; no. 6. .
Audio-visual equipment.--------
Audio-visual materials.--------