Observerare

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  Ewan Plott

  https://www.diigo.com/outliner/noxm6v/%EA%B3%B5%EC%8B%9D-%EC%9D%B8%EC%A6%9D-%EC%B9%B4%EC%A7%80%EB%85%B8-%EC%84%A0%ED%83%9D%EC%9D%98-%EC%A4%91%EC%9A%94%EC%84%B1?key=58n1ulfkq6