Columbia subject headings:
Historians--Soviet Union--Biography.
Ivanov, L. M. (Leonid Mikhaĭlovich), 1909-1972.
Labor movement--Soviet Union--History.
Working class--Soviet Union--History.
Harvard subject headings:
Historians--Soviet Union--Biography
Ivanov, L. M. (Leonid Mikhaĭlovich), 1909-1972
Labor movement--Soviet Union--History.
Working class--Soviet Union--History
Princeton subject headings:
Historians--Soviet Union--Biography.
Ivanov, L. M. (Leonid Mikhaĭlovich), 1909-1972.
Labor movement--Soviet Union--History.
Working class--Soviet Union--History.