1. 1) S. Sakamoto, ``Roles achieved by Research Committee on Road Traffic Noise and future subjects to be solved by the Committee,'' Proc. Autumn Meet. Acoust. Soc. Jpn., pp. 1543-1546 (2012) (in Japanese).
2. 2) K. Ishii, ``Prediction of road traffic noise (part 1), method of practical calculation,'' J. Acoust. Soc. Jpn. (J), 31, 507-517 (1975) (in Japanese).
3. 3) K. Ikegaya, ``Mathematical models and estimation for predicting the road traffic noise,'' J. Acoust. Soc. Jpn. (J), 31, 559-565 (1975) (in Japanese).
4. 4) K. Ishii, ``Prediction of road traffic noise,'' J. Acoust. Soc. Jpn. (J), 33, 462-430 (1977) (in Japanese).
5. 5) M. Sasaki and M. Yamashita, ``Discussion on the prediction method of traffic noise in the vicinity of the road tunnel,'' J. Acoust. Soc. Jpn. (J), 40, 554-558 (1984) (in Japanese).