1. 1) Ministry of the Environment: Junkangata-Syakai-Hakusyo (in Japanese) (2005).
2. 2) Association for electric home appliances: Kadensangyou Handbook 2005 (in Japanese) (2005).
3. 3) Association for electric home appliances: Haikadenseihin-hasseiryou-no-yosokuchousakenkyuu-houkokusyo (in Japanese) (1993).
4. 4) Ministry of Economy, Trade and Industry: Haikibutsutou-syori-saishigenka-suishin-jigyou Houkokusyo (in Japanese) (1998).
5. 5) The Japan Electrical Manufacturers' Association: 2003nen-ni-itaru-kadenseihinn-no-kokunaijuyouyosoku (in Japanese) (1999).