Book "Kotetsu and Kiyomaro", Sano Museum
160 pages in Japanese with a list of plates in English. The Sano Museum publishes wonderful books and this is no exception. 35 pieces by Kotetsu: swords, a couple kogatana, a tsuba, and a pair of armor sleeves, and 71 pieces by Kiyomaro: swords and 4 kogatana. 1st class photography, incredible detail.