https://www.inopressa.ru/article/25Dec2018/newsweek/attack.html
http://www.ng.ru/politics/2018-12-25/1_7473_army.html
http://www.ng.ru/politics/2018-12-25/3_7473_doklad.html
https://www.gazeta.ru/politics/2018/12/24_a_12107005.shtml
https://www.gazeta.ru/business/2018/12/25/12107293.shtml
https://www.gazeta.ru/politics/2018/12/25_a_12107371.shtml
https://www.gazeta.ru/business/2018/12/25/12107755.shtml
https://www.kommersant.ru/doc/3842884
https://www.kommersant.ru/doc/3842391
Regional experts also predicted that Russia may look to take advantage of the uncertainty created by James Mattis's resignation as President Trump's defense secretary.
https://www.newsweek.com/ukraine-russia-war-attack-christmas-1270621