@inproceedings{CTT100643093,
  author = {Xianfeng Zhang and Tsuyoshi Kobayashi and Satoshi Oonishi and Yoshiaki Hirai and Yuta Nakajima and Yasuyoshi Kurokawa and Akira Yamada},
  title = {Progress Towards Realization of Chalcopyrite-Based Tandem Solar Cells},
  booktitle = {},
  year = 2012,
}

@inproceedings{CTT100643055,
  author = {Akira Yamada and Xianfeng Zhang and Satoshi Oonishi and Hiroshi Nagashima and Yukiya Hidaka and Yuta Nakajima and Tsuyoshi Kobayashi and Yoshiaki Hirai and Yasuyoshi Kurokawa},
  title = {Approaches to realization of Cu(InGa)Se2-based tandem solar cells},
  booktitle = {},
  year = 2010,
}