1. Cabinet Office: The Aging Society: Current Situation and Implementation Measures Annual Report, 2013.
2. Ministry of Health, Labour and Welfare: Comprehensive Survey of Living Conditions, 2012.
3. Osaka Gas Security Service: Omamori Call, http://www.oss-og.co.jp/service/omamori/index.html.
4. Zojirushi: Mimamori Hotline, http://www.mimamori.net/service/index.html.
5. Home-Eye: the Kansai Electric Power Group.