Observerare

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  Chang Masel

  https://nedirbilgi.com/%EC%9A%B0%EB%A6%AC%EC%B9%B4%EC%A7%80%EB%85%B8-%EC%8B%A4%EC%8B%9C%EA%B0%84-%EA%B3%A0%EA%B0%9D%EC%84%BC%ED%84%B0%EC%9D%98-%EB%AA%A8%EB%93%A0-%EA%B2%83-%EB%8D%94%EC%9A%B1-%EC%95%88%EC%A0%84%ED%95%98/