Columbia subject headings:
North Sea Region--Antiquities.
North Sea Region--Civilization.
Prehistoric peoples--North Sea Region.
Harvard subject headings:
Blackburn, Julia--Travel--North Sea Region.
England--Description and travel.
Europe, Northern--Description and travel.
Mesolithic period--North Sea Region.
North Sea Region--Antiquities.
North Sea Region--Civilization.
North Sea Region--Description and travel.
Prehistoric peoples--North Sea Region.
Submerged lands--North Sea Region--History.
Princeton subject headings:
Blackburn, Julia--Travel--North Sea Region.
England--Description and travel.
Europe, Northern--Description and travel.
Mesolithic period--North Sea Region.
North Sea Region--Antiquities.
North Sea Region--Civilization.
North Sea Region--Description and travel.
Prehistoric peoples--North Sea Region.
Submerged lands--North Sea Region--History.