電撃オンライン『塊魂』インタビュー (in Japanese). Dengeki Online. Archived from the original on June 26, 2004. Retrieved May 18, 2006.
espacenet.com
worldwide.espacenet.com
US patent 7402104, Masatoshi Ogita, Kazumi Yamabe, Keita Takahashi; Yamabe, Kazumi & Takahashi, Keita, "Game performing method, game apparatus, storage medium, data signal and program", issued June 22, 2008, assigned to Namco Bandai Games
"2004年ゲームソフト年間売上TOP300" [2004 Game Software Annual Sales Top 300]. Famitsū Gēmu Hakusho 2005 ファミ通ゲーム白書2005 [Famitsu Game Whitebook 2005] (in Japanese). Tokyo: Enterbrain. 2005. Archived from the original on June 27, 2015. Retrieved May 27, 2015.
"2004年ゲームソフト年間売上TOP300" [2004 Game Software Annual Sales Top 300]. Famitsū Gēmu Hakusho 2005 ファミ通ゲーム白書2005 [Famitsu Game Whitebook 2005] (in Japanese). Tokyo: Enterbrain. 2005. Archived from the original on June 27, 2015. Retrieved May 27, 2015.
Gantayat, Anoop (March 9, 2004). "Namco Plans Big". IGN. Archived from the original on March 24, 2014. Retrieved March 24, 2014.