Analysis of information sources in references of the Wikipedia article "Hironori Ōtsuka" in English language version.
{{cite web}}: |last= has generic name (help)Hironori Ohtsuka (1892-1982) Ohtsuka, whose father was a medical doctor, was born in Shimodate City, Japan. Ohtsuka was first introduced to martial arts by his great uncle, Chojiro Ebashi, a samurai warrior, who began teaching him jujitsu. When he was thirteen, he studied the style under Shinzaburo Nakayama, a grandmaster of jujitsu. He continued with his studies through school and university. In 1922 Ohtsuka met Gichin Funakoshi and began to learn more about karate while still continuing with his studies of jujitsu. Ohtsuka also studied other Japanese martial arts including judo, kendo and aikido. He blended the practical and useful elements of Okinawan karate with the techniques found in jujitsu and kendo, which led to the birth of kumite in karate. At this stage Ohtsuka thought that there was a need for this more dynamic and fluid type of karate to be taught, so he decided to leave Funakoshi to concentrate on developing his own style of karate-Wado. In 1934, Wado-ryu karate was officially recognized as an independent style of karate. Ohtsuka left his medical practice and became a full-time martial artist. In 1944, Ohtsuka was appointed Japan's Chief Karate Instructor.
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