Columbia subject headings:
Public health--United States.
Washington (D.C.)--Sanitary affairs.
Washington (D.C.)--Social conditions.
Harvard subject headings:
Public health
Public health--United States
Public health--Washington (D.C.)
Sanitation--United States.
Sanitation--Washington (D.C.)
Sanitation.
Washington (D.C.)--Social conditions.
Princeton subject headings: