Não informado. University of Iowa studies in character. Institute of Character Research.
Chicago-referens (17:e uppl.)Não informado. University of Iowa Studies in Character. Iowa City, Iowa: Institute of Character Research.
MLA-referens (8:e uppl.)Não informado. University of Iowa Studies in Character. Institute of Character Research.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.