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2. Factor analysis of descriptive adjective for the evaluation of sounds;Sone;Science Reports of the Research Institutes, Tohoku University, Series B,1963
3. O. Kitamura, S. Namba, R. Matsumoto, Factor analytical research of tone colour, Proceedings of Sixth International Congress on Acoustics, Vol. A-5-11, 1968.
4. Multiple rating of sound stimuli;Kerrick;Journal of the Acoustical Society of America,1968
5. On the loudness of traffic noise;Namba;Journal of Acoustical Society of Japan,1976