Columbia subject headings:
Forging industry--United States--History.
SIFCO Industries--History.
Steel industry and trade--United States--History.
Harvard subject headings:
Forging industry--United States--History.
SIFCO Industries--History.
Steel industry and trade--United States--History
Princeton subject headings:
Forging industry--United States--History.
SIFCO Industries--History.
Steel industry and trade--United States--History.