Template:Matsumoto, Nishida & Toshimitsu, 2003
- Matsumoto, T., Nishida, T. & Toshimitsu, S. 2003. Early Cenomanian (Cretaceous) ammonoids Utaturiceras and Graysonites from Hokkaido, North Japan (Studies of the Cretaceous ammonites from Hokkaido and Sakhalin–XCV). Bulletin of the Geological Survey of Japan 54(3-4): 131–159.