Columbia subject headings:
Hertfordshire (England)--Census, 1851.
Hertfordshire (England)--Economic conditions--Statistics.
Hertfordshire (England)--Population--Statistics.
Households--England--Hertfordshire--Statistics.
Harvard subject headings:
Hertfordshire (England)--Census, 1851.
Hertfordshire (England)--Economic conditions--Statistics.
Hertfordshire (England)--Population--Statistics.
Households--England--Hertfordshire--Statistics.
Princeton subject headings:
Church records and registers--England--Hertfordshire.
Family demography--England--Hertfordshire.
Hertfordshire (England)--Economic conditions.
Hertfordshire (England)--Genealogy.
Hertfordshire (England)--History--Sources.
Hertfordshire (England)--Population.