прерывались https://ru.wikipedia.org/wiki/%D0%93%D0%B0%D0%B7%D0%BE%D0%B2%D1%8B%D0%B5_%D0%BA%D0%BE%D0%BD%D1%84%D0%BB%D0%B8%D0%BA%D1%82%D1%8B_%D0%BC%D0%B5%D0%B6%D0%B4%D1%83_%D0%A0%D0%BE%D1%81%D1%81%D0%B8%D0%B5%D0%B9_%D0%B8_%D0%A3%D0%BA%D1%80%D0%B0%D0%B8%D0%BD%D0%BE%D0%B9