Berlin Demography Forum
↑ Deville & Ischinger 2012, p. 46.
↑ Article Allianz News, retrieved May 19. 2014.
↑ Article of the German Federal Ministry for Family Affairs, Senior Citizens, Women and Youth April 10. 2014 about BDF 2014, retrieved at May 19. 2014.
↑ News Vodafone Foundation, retrieved May 19. 2014.