Columbia subject headings:
Harvard subject headings:
Big business--Middle West--Public opinion--History.
Monopolies--Middle West--History.
Public opinion--Middle West--History.
Trusts, Industrial--Middle West--History.
Princeton subject headings:
Big business--Middle West--Public opinion--History.
Monopolies--Middle West--History.
Public opinion--Middle West--History.
Trusts, Industrial--Middle West--History.