Sources:
Kholiavsky, G.L. The Complete Encyclopedia of World Tanks 1915-2000, Moscow, 1998
Mikulin A.A. Stechkin in my life.  
The Russian WW1 Lebedenko (or Tsar) Tank. https://web.archive.org/web/20080709014139/http://www.landships.freeservers.com/lebedenko_info.htm 
Тарасов, Алексей. "Царь-танк: Огромный, беспощадный и бессмысленный." Техкульт. November 09, 2014. https://www.techcult.ru/technics/1954-tsar-tank-lebedenko