Columbia subject headings:
Chemical industry--History.
Chemical industry--United States--History.
E.I. du Pont de Nemours & Company--History.
Harvard subject headings:
Chemical industry--History.
Chemical industry--United States--History
E.I. du Pont de Nemours & Company--History.
Princeton subject headings:
Chemical industry--History.
Chemical industry--United States--History.
E.I. du Pont de Nemours & Company--History.