1. Nationalmuseum Tokyo Materials, catalogues etc
2. Ogasawara , N. Kinds of Japanese swords 1994
3. Nihontô, Kôza, Lectures about Japanese swords 1/20 1934
4. Ogasawara , N. History and appreciation of Japanese swords Kôdansha 1987
5. Shibata , M. Style of Japanese swords Yûzankaku 1991