Submodule of free Z-module
Futa, Yuichi, Okazaki, Hiroyuki, Shidama, Yasunari
Continuity of Multilinear Operator on Normed Linear Spaces
Nakasho, Kazuhisa, Shidama, Yasunari
The Product Space of Real Normed Spaces and its Properties
Endou, Noboru, Shidama, Yasunari, Miyajima, Keiichi