"Hokuriku". Seamless Digital Geological Map of Japan. Geological Survey of Japan, AIST. 2007. Archived from the original on 6 February 2009. Retrieved 2 February 2009.
"ASAMA-YAMA". Quaternary Volcanoes in Japan. Geological Survey of Japan, AIST. 2006. Archived from the original on 19 December 2012. Retrieved 3 February 2009.
"ASAMA-YAMA". Quaternary Volcanoes in Japan. Geological Survey of Japan, AIST. 2006. Archived from the original on 19 December 2012. Retrieved 3 February 2009.
"Hokuriku". Seamless Digital Geological Map of Japan. Geological Survey of Japan, AIST. 2007. Archived from the original on 6 February 2009. Retrieved 2 February 2009.