Columbia subject headings:
Ecology--Former Soviet republics--Congresses.
Ecology--Russia (Federation)--Congresses.
Human ecology--Former Soviet republics--Congresses.
Human ecology--Russia (Federation)--Congresses.
Harvard subject headings:
Ecology--Former Soviet republics--Congresses.
Ecology--Russia (Federation)--Congresses
Human ecology--Former Soviet republics--Congresses.
Human ecology--Russia (Federation)--Congresses
Princeton subject headings:
Ecology--Former Soviet republics--Congresses.
Ecology--Russia (Federation)--Congresses.
Human ecology--Former Soviet republics--Congresses.
Human ecology--Russia (Federation)--Congresses.