Complexity and Completeness of Finding Another Solution and Its Application to Puzzles. - Takayuki Yato; Takahiro Seta (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2003)

Finding Yozume of Generalized Tsume-Shogi is Exptime-Complete. - Takayuki Yato; Takahiro Seta; Tsuyoshi Ito (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2005)