Columbia subject headings:
Mari El (Russia)--Politics and government.
Petrov, I. P. (Ivan Petrovich) 1893-1938.
Politicians--Russia (Federation)--Mari El--Biography.
Harvard subject headings:
Mari El (Russia)--Politics and government--20th century.
Mari El (Russia)--Politics and government.
Petrov, I. P. (Ivan Petrovich), 1893-1938.
Politicians--Russia (Federation)--Mari El--Biography.
Princeton subject headings:
Mari El (Russia)--Biography.
Mari El (Russia)--Civilization--20th century.
Petrov, I. P. (Ivan Petrovich) 1893-1938.