Observerare

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  Roscoe Fairbank

  https://okzoa.kr/%ec%98%a8%eb%9d%bc%ec%9d%b8%eb%8f%84%eb%b0%95-%ec%95%88%ec%a0%84%ed%95%98%ea%b2%8c-%ec%a6%90%ea%b8%b0%eb%8a%94-%eb%b0%a9%eb%b2%95-%ec%8a%88%ec%96%b4%eb%a7%a8%ea%b3%bc-%eb%a8%b9%ed%8a%80%ea%b2%80/