Columbia subject headings:
Antitrust law--United States--Periodicals.
Coal trade--United States--Periodicals.
Trusts, Industrial--United States--Periodicals.
Harvard subject headings:
Antitrust law--United States--Periodicals
Coal trade--United States--Periodicals.
Trusts, Industrial--United States--Periodicals.
Princeton subject headings:
Antitrust law--United States--Periodicals.
Coal trade--United States--Periodicals.
Periodicals.
Trusts, Industrial--United States--Periodicals.