Both have an extended English abstract that gives a good overview.
Emergence of the discourse about “sportification of judo” during the process leading to establishment of the Four Imperial Universities Competition and its historic significance, focusing on the relationship between “student judo” and Kōdōkan judo from 1918 to 1928
Tetsuya Nakajima
Taiikugaku kenkyu (Japan Journal of Physical Education, Health and Sport Sciences)
(2014)
[Advance Publication] Released: October 15, 2014
https://www.jstage.jst.go.jp/article/jjpehss/advpub/0/advpub_13097/_pdf
The establishment process of Kosen Judo Taikai: Emergence of competitive spirit and the formation process of refereeing regulations
Tetsuya Nakajima
Taiikugaku kenkyu (Japan Journal of Physical Education, Health and Sport Sciences)
Vol. 58 (2013) No. 1
Released: June 08, 2013
[Advance Publication] Released: May 13, 2013 pp257-276
https://www.jstage.jst.go.jp/article/jjpehss/58/1/58_12075/_pdf
Emergence of the discourse about “sportification of judo” during the process leading to establishment of the Four Imperial Universities Competition and its historic significance, focusing on the relationship between “student judo” and Kōdōkan judo from 1918 to 1928
Tetsuya Nakajima
Taiikugaku kenkyu (Japan Journal of Physical Education, Health and Sport Sciences)
(2014)
[Advance Publication] Released: October 15, 2014
https://www.jstage.jst.go.jp/article/jjpehss/advpub/0/advpub_13097/_pdf
The establishment process of Kosen Judo Taikai: Emergence of competitive spirit and the formation process of refereeing regulations
Tetsuya Nakajima
Taiikugaku kenkyu (Japan Journal of Physical Education, Health and Sport Sciences)
Vol. 58 (2013) No. 1
Released: June 08, 2013
[Advance Publication] Released: May 13, 2013 pp257-276
https://www.jstage.jst.go.jp/article/jjpehss/58/1/58_12075/_pdf