Ōkawa, R. (2003). An unshakable mind: How to overcome life?s difficulties. Lantern Books.
Chicago-referens (17:e uppl.)Ōkawa, Ryūhō. An Unshakable Mind: How to Overcome Life?s Difficulties. New York: Lantern Books, 2003.
MLA-referens (9:e uppl.)Ōkawa, Ryūhō. An Unshakable Mind: How to Overcome Life?s Difficulties. Lantern Books, 2003.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.