Observerare

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  Rogelio Michels

  https://jeoji.net/%EC%8A%A4%ED%94%BC%EB%93%9C%ED%82%A4%EB%85%B8-%EC%8B%A4%EC%8B%9C%EA%B0%84-%EA%B2%B0%EA%B3%BC-%EC%8B%A0%EC%86%8D%ED%95%98%EA%B3%A0-%EC%A0%95%ED%99%95%ED%95%9C-%EC%A0%95%EB%B3%B4-%EC%A0%9C%EA%B3%B5/