Isomorphism Theorem on Vector Spaces over a Ring
Futa, Yuichi, Shidama, Yasunari
Implicit Function Theorem. Part I
Nakasho, Kazuhisa, Futa, Yuichi, Shidama, Yasunari
Maximum Number of Steps Taken by Modular Exponentiation and Euclidean Algorithm
Okazaki, Hiroyuki, Nagao, Koh-ichi, Futa, Yuichi