Wolf Tony. (2009). The book of the earth, many questions and many answers. Euro Books.
Chicago-referens (17:e uppl.)Wolf Tony. The Book of the Earth, Many Questions and Many Answers. Mumbai: Euro Books, 2009.
MLA-referens (9:e uppl.)Wolf Tony. The Book of the Earth, Many Questions and Many Answers. Euro Books, 2009.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.