Watchers

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  Mathias Johansen

  https://inventmag.com/%ea%b4%91%ec%a3%bc%ec%97%90%ec%84%9c%ec%9d%98-%ed%8a%b9%eb%b3%84%ed%95%9c-%eb%b0%a4-%ea%b4%91%ec%a3%bc%eb%b0%a4%ec%95%8c%eb%b0%94%ec%9d%98-%eb%a7%a4%eb%a0%a5/