Encyc. Brit., 15th (Ivan IV, the Terrible, of Russia)
Milīus, Ḟ. Oprichnik, ili, Chetvertyĭ brak Ivana Vasilʹevicha Groznago, 1865.
NUC pre-1956 under Oderborn, Paul (t.p. usage, inter alia, Jwan Wasilowitz)
Oderborn, P. Ioannis Basilidis, Magni Moscouiae Ducis vita, 1585 t.p. (Ioannis Basilidis, Magni Moscouiae Ducis ...) leaf V4b (d. 3-28-1584, having lived 56 years, 7 months)
Russ. Brockhaus (Īoann Vasilʹevich, Czar and Grand Duke of Russia, called Groznyĭ)
Troyat, H. Ivan le Terrible, c1982 t.p. etc. (Ivan le Terrible)