Nelson, Gail E. (February 1986). "Aikijujutsu vs. Aikido". Black Belt Magazine. 24 (2): 34–38. Archived from the original on 19 October 2023. Retrieved 27 February 2017.
Nelson, Gail E. (February 1986). "Aikijujutsu vs. Aikido". Black Belt Magazine. 24 (2): 34–38. Archived from the original on 19 October 2023. Retrieved 27 February 2017.
Takeda, Tokimune (2006). "Sōkaku Takeda in Osaka". Aikidojournal.com. Archived from the original on 5 June 2011. Retrieved 4 August 2014.{{cite web}}: CS1 maint: bot: original URL status unknown (link)