Ring ni Kakero (Japanese: リングにかけろ, Hepburn: Ringu ni Kakero, lit. "Put It All in the Ring") is a Japanese manga series written and illustrated by Masami Kurumada. It was published in Weekly Shōnen Jump between January 1977 and October 1981. The individual chapters were compiled by Shueisha into twenty-five tankōbon volumes. A sequel entitled Ring ni Kakero 2 was serialized in Super Jump between 2000 and 2008. An anime adaptation produced by Toei Animation premiered in October 2004. It was followed by a second season premiered in April 2006, a third season in April 2010 and a fourth season in April 2011. Ring ni Kakero is one of Weekly Shōnen Jump's best-selling manga series, with over 13 million copies sold. Source: Wikipedia (en)