Observerare

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  Garland Matthaei

  https://lanpii.net/%EB%A3%B0%EB%9D%BC%EB%B2%B3-%EC%8A%A4%ED%8F%AC%EC%B8%A0%ED%86%A0%ED%86%A0-%EC%B5%9C%EC%8B%A0-%ED%8A%B8%EB%A0%8C%EB%93%9C%EC%99%80-%ED%99%9C%EC%9A%A9%EB%B2%95/