Columbia subject headings:
Harvard subject headings:
Human ecology--Russia.
Human ecology--Soviet Union
Nature--Effect of human beings on--Russia--History.
Nature--Effect of human beings on--Soviet Union--History.
Russia--Environmental conditions.
Soviet Union--Environmental conditions.
Princeton subject headings:
Geology--Eurasia--Congresses.
Geology--Russia--Congresses.
Geology--Soviet Union--Congresses.
Human ecology--Eurasia--History--Congresses.
Human ecology--Russia--History--Congresses.
Human ecology--Soviet Union--History--Congresses.
Natural history--Eurasia--Congresses.
Natural history--Russia--Congresses.
Natural history--Soviet Union--Congresses.