Columbia subject headings:
Medicine--Portugal--Porto--History--16th century.
Medicine--Portugal--Porto--History--17th century.
Medicine--Portugal--Porto--History--To 1500.
Naval hygiene--Portugal--Porto--History.
Public health--Portugal--Porto--History.
Ships--Health regulations--Portugal--Porto--History.
Harvard subject headings:
Naval hygiene--Portugal--Porto--History.
Porto (Portugal)--Social conditions.
Public health--Portugal--Porto--History.
Ships--Health regulations--Portugal--Porto--History.
Princeton subject headings:
Medicine--Portugal--Porto--History--16th century.
Medicine--Portugal--Porto--History--17th century.
Medicine--Portugal--Porto--History--To 1500.