https://www.vedomosti.ru/politics/articles/2017/12/08/744578-tretii-srok-putina
https://republic.ru/posts/88246
https://www.kommersant.ru/doc/3489380
Opposition politician’s campaign gathers steam ahead of 2018 election, but his supporters face threats and intimidation
http://www.ej.ru/?a=note&id=31883
https://www.radiosvoboda.org/a/28902822.html
https://www.radiosvoboda.org/a/28900767.html
https://www.gazeta.ru/business/2017/12/07/11196230.shtml
https://www.novayagazeta.ru/articles/2017/12/07/74827-soyuz-apollonov