Спостерігачі

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  Kent Gibb

  https://www.natscibooks.com/%EC%95%88%EC%A0%84%ED%95%98%EA%B2%8C-%EC%A6%90%EA%B8%B8-%EC%88%98-%EC%9E%88%EB%8A%94-%EB%A9%94%EC%9D%B4%EC%A0%80%EC%82%AC%EC%9D%B4%ED%8A%B8-%EA%B2%80%EC%A6%9D%EB%90%9C-%EB%A8%B9%ED%8A%80-%EC%97%86/