Tichomirovas, Sergejus. „Sergey Kovalev’s Activities in the Dissident Movement and His Ties With Lithuania“. Genocidas ir rezistencija 1, no. 21 (balandžio 27, 2007): 105–125. žiūrėta vasario 21, 2026. https://www.zurnalai.vu.lt/gr/article/view/38647.