Columbia subject headings:
Harvard subject headings:
Great Britain--History--Civil War, 1642-1649.
Great Britain--History--Puritan Revolution, 1642-1660
Levellers--History.
Radicals--Great Britain--History.
Princeton subject headings:
Great Britain--History--Civil War, 1642-1649.
Great Britain--History--Commonwealth and Protectorate, 1649-1660.
Levellers--History.