Спостерігачі

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  Michal Keble

  https://sciencealert.co.uk/%ED%86%A0%ED%86%A0%EC%82%AC%EC%9D%B4%ED%8A%B8%EC%9D%98-%EC%84%B8%EA%B3%84-%EC%95%88%EC%A0%84%ED%95%98%EA%B3%A0-%ED%95%A9%EB%B2%95%EC%A0%81%EC%9D%B8-%EC%9D%B4%EC%9A%A9%EC%9D%84-%EC%9C%84%ED%95%9C/