"RYO KASHIMA","A proof of the completeness theorem for the modal logic with  transitive closure of accessibility relation",,"Research Reports on Mathematical and Computing Sciences","Tokyo Institute of Technology","  C-266",,,2009,Dec.
"RYO KASHIMA","数理論理学",,,"朝倉書店",,,,2009,Oct.
"RYO KASHIMA","到達可能関係の推移的閉包を扱う様相論理の完全性",,"日本数学会  数学基礎論分科会 講演アブストラクト",,,,,2009,Sept.