Columbia subject headings:
Harvard subject headings:
Environmental protection--Russia (Federation)--Tverskai͡a oblastʹ--Periodicals.
Pollution--Russia (Federation)--Tverskai͡a oblastʹ--Periodicals.
Princeton subject headings:
Environmental protection--Russia (Federation)--Tverskai︠a︡ oblastʹ.
Pollution--Russia (Federation)--Tverskai︠a︡ oblastʹ.