National Geophysical Data Center / World Data Service (NGDC/WDS): NCEI/WDS Global Significant Earthquake Database. NOAA National Centers for Environmental Information (1972). "NOAA Earthquake Database Query". NOAA National Centers for Environmental Information. doi:10.7289/V5TD9V7K.
noaa.gov
ngdc.noaa.gov
National Geophysical Data Center / World Data Service (NGDC/WDS): NCEI/WDS Global Significant Earthquake Database. NOAA National Centers for Environmental Information (1972). "NOAA Earthquake Database Query". NOAA National Centers for Environmental Information. doi:10.7289/V5TD9V7K.
toyokeizai.net
鎌倉幕府は何年に成立?正解を言えますか (in Japanese). Toyo keizai. 9 June 2016. Archived from the original on 9 May 2022. Retrieved 9 March 2024.
web.archive.org
鎌倉幕府は何年に成立?正解を言えますか (in Japanese). Toyo keizai. 9 June 2016. Archived from the original on 9 May 2022. Retrieved 9 March 2024.
worldcat.org
Hane, Mikiso (2015). Premodern Japan: A Historical Survey. Perez, Louis (2nd ed.). Boulder, CO: Westview Press. p. 95. ISBN9780813349701. OCLC895428280.