@article{oai:nifs-repository.repo.nii.ac.jp:00003543, author = {"Akiyama, T. and Kawahata, K. and Tokuzawa, T. and Ashikawa, N. and Tokitani, M. and Okajima, S. and Nakayama, K. and Yoshida, N. and Tokunaga, K."}, journal = {Annual Report of National Institute for Fusion Science}, title = {Change of Optical Properties of Retro-reflector Installed in LHD}, volume = {Annual Report Apr.2007 - Mar.2008} }