河上 哲. Extensions of Pontryagin hypergroups. 数理解析研究所講究録「作用素環論の発展」. 2006. 1531. 96-108
河上哲. On the claim that a classification theory in functional analysis is impossibl. Proceeding of the Workshop on operator theory and operator algebras. 2005. 64?74
河上哲. Commutative hypergroups associated with group action. 京都大学数理解析講究録「作用素環論とその周辺」. 2005
河上哲. 群作用に付随したハイパー群. 作用素論・作用素環論報告集. 2004
書籍 (2件)：
Relative Entropy of a Fixed Point Algebra, "Mappings of Operator Algebras"
Birkhauser 1990
On the Weak Cohomology Groups and the Diversity of MASA's in the Hyperfinite Type II Factor, "Geometric Method in operator algebras"
Pitman 1986
講演・口頭発表等 (28件)：
A hypergroup arising from characters of a compact hypergroup and its subhypergroup
(日本数学会 函数解析分科会 2015)
A commutative hypergroup associated with a hyperfield
(日本数学会 函数解析分科会 2015)
