Columbia subject headings:
Harvard subject headings:
Eugenics--Great Britain.
Malthus, T. R. (Thomas Robert), 1766-1834.
Malthusianism.
Medicine--History--19th century.
Princeton subject headings:
Eugenics--History--19th century.
Medicine--History--19th century.
Physicians--Great Britain--19th century.
Population dynamics--Great Britain--19th century.