Columbia subject headings:
Russia--Foreign relations--Spain--18th century.
Russia--Politics and government--1689-1801.
Spain--Foreign relations--Russia--18th century.
Harvard subject headings:
Russia--Foreign relations--1689-1801.
Russia--Foreign relations--Spain.
Russia--Politics and government--1689-1801.
Spain--Foreign relations--18th century.
Spain--Foreign relations--Russia.
Princeton subject headings:
Russia--Foreign relations--Spain--18th century.
Russia--Politics and government--1689-1801.
Spain--Foreign relations--Russia--18th century.