Columbia subject headings:
Aerospace industries--United States.
Aircraft industry--United States.
Steel industry and trade--United States--History.
Wyman-Gordon Company--History.
Harvard subject headings:
Aerospace industries--United States
Aircraft industry--United States
Forging industry--Massachusetts--History.
Steel industry and trade--United States--History
Wyman-Gordon Company--History.
Princeton subject headings:
Aerospace industries--United States.
Aircraft industry--United States.
Steel industry and trade--United States--History.
Wyman-Gordon Company--History.