An upper bound for the cardinality of an $s$-distance set in Euclidean space (with Kazuki Kawasaki, Yusuke Nitamizu, and Teppei Sato). Combinatorica. 2003. 23 , 535--557
Modular invariants of the modular data of finite groups(with Eiichi Bannai,Osamu Shimabukuro and Makoto Tagami). Matimyas Matematika (Official Journal of Mathematical Society of Philippines),. 2002. Vol 25 , special issue, 12-24