Columbia subject headings:
Harvard subject headings:
Pskovskai︠a︡ oblastʹ (Russia)--Economic conditions.
Pskovskai︠a︡ oblastʹ (Russia)--Social conditions.
Princeton subject headings:
Pskovskai︠a︡ oblastʹ (Russia)--Economic conditions.
Pskovskai︠a︡ oblastʹ (Russia)--Social conditions.