1. 1) K. Tanaka, A. Sato and Y. Kakimoto, ``A study on car communication,'' Bull. Jissen Women's Univ. Fac. Hum. Life Sci., 43, 104-113 (2006) (in Japanese).
2. 2) Ministry of Land, Infrastructure, Transport and Tourism (amended in 2014), Japanese Road Traffic Law, Chap. 3, Sect. 10, Art. 54.
3. 3) Ministry of Land, Infrastructure, Transport and Tourism (amended in 2012), Safety Standard for Road Transportation Vehicles, Chap. 2, Art. 43.
4. 4) M. Takada, Y. Fukuda and S. Iwamiya, ``Questionnaire survey on vehicle horn use and its effects on drivers and pedestrians,'' Acoust. Sci. & Tech., 34, 187-196 (2013).
5. 5) M. Takada, A. Takeno and S. Iwamiya, ``Effects of vehicle horn acoustic properties on auditory impressions and the interpretation of reasons for horn use by other drivers,'' Noise Control Eng. J., 58, 259-272 (2010).