Список литературы:

1.http://ru.wikipedia.org/wiki/%C3%E0%E7%EE%F2%F3%F0%E1%E8%ED%ED%FB%E9_%E4%E2%E8%E3%E0%F2%E5%EB%FC

2.http://slovari.yandex.ru/~%D0%BA%D0%BD%D0%B8%D0%B3%D0%B8/%D0%91%D0%A1%D0%AD/%D0%93%D0%B0%D0%B7%D0%BE%D1%82%D1%83%D1%80%D0%B1%D0%B8%D0%BD%D0%BD%D1%8B%D0%B9%20%D0%B4%D0%B2%D0%B8%D0%B3%D0%B0%D1%82%D0%B5%D0%BB%D1%8C/