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  journal = {Sustainability},
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}

@article{CTT100823695,
  author = {T. Ogawa and M. Takeuchi and Y. Kajikawa},
  title = {Analysis of trends and emerging technologies in water electrolysis research based on a computational method: a comparison with fuel cell research},
  journal = {Sustainability},
  year = 2018,
}

@article{CTT100823696,
  author = {T. Ogawa and M. Takeuchi and Y. Kajikawa},
  title = {Comprehensive analysis of trends and emerging technologies in all types of fuel cells based on a computational method},
  journal = {Sustainability},
  year = 2018,
}