Спостерігачі

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  Issac Earnshaw

  https://network.janenk.com/read-blog/27381_%D0%BA%D0%B0%D0%BA-%D0%BE%D0%B1%D0%BC%D0%B5%D0%BD%D1%8F%D1%82%D1%8C-%D0%B4%D0%B5%D0%BD%D1%8C%D0%B3%D0%B8-%D0%B2-%D1%81%D1%88%D0%B0.html