Katori Jingu: https://katori-jingu.or.jp/
Japan Kobudo Promotion Society (Kobudo Shinkokai): http://kobushin.jp/
Nihon Kobudo Association (Nihon Kobudo Kyokai): http://www.nihonkobudokyoukai.org/
Tenshinsho-den Katori Shinto-ryu Kyoso Shibu: http://katori-shinto-ryu.org/