Columbia subject headings:
Sewage disposal--Illinois--Chicago.
Sewerage--Illinois--Chicago.
Water-supply--Illinois--Chicago.
Harvard subject headings:
Chicago (Ill.)--Sewerage.
Chicago (Ill.)--Water-supply.
Sewage disposal--Illinois--Chicago.
Sewerage--Illinois--Chicago
Water-supply--Illinois--Chicago
Princeton subject headings:
Sewage disposal--Illinois--Chicago.
Sewerage--Illinois--Chicago.
Water-supply--Illinois--Chicago.