Columbia subject headings:
Historians--Orel (Orlovskai͡a oblastʹ)--Russia--Bio-bibliography.
Orel (Orlovskai︠a︡ oblastʹ, Russia)--History--Study and teaching.
Harvard subject headings:
Historians--Russia (Federation)--Orel (Orlovskai︠a︡ oblastʹ)--Bio-bibliography.
Orel (Orlovskai︠a︡ oblastʹ, Russia)--History--Study and teaching--Bio-bibliography.
Princeton subject headings: