Columbia subject headings:
Harvard subject headings:
Catholic Church--Foreign relations--Soviet Union.
Counter-Reformation.
Possevino, Antonio, 1533 or 1534-1611.
Princeton subject headings:
Catholic Church--Foreign relations--Soviet Union.
Counter-Reformation.
Ivan IV, Czar of Russia, 1530-1584.
Possevino, Antonio, 1533-1611.