Columbia subject headings:
Cardiology--Great Britain--History--19th century.
Cardiology--Great Britain--History--20th century.
Cardiology--United States--History--19th century.
Cardiology--United States--History--20th century.
Soldiers--Diseases--Great Britain--History--19th century.
Soldiers--Diseases--Great Britain--History--20th century.
Soldiers--Diseases--United States--History--19th century.
Soldiers--Diseases--United States--History--20th century.
Harvard subject headings:
Cardiology--Great Britain--History--19th century.
Cardiology--Great Britain--History--20th century.
Cardiology--United States--History--19th century.
Cardiology--United States--History--20th century.
United States--History--Civil War, 1861-1865--Medical care.
World War, 1914-1918--Medical care
Princeton subject headings: