Columbia subject headings:
Business--History--20th century.
Commerce--History--20th century.
Economic history--20th century.
Harvard subject headings:
Business--History--20th century--Chronology.
Business--History--20th century.
Commerce--History--20th century--Chronology.
Commerce--History--20th century.
Economic history--20th century
Economic history--20th century--Chronology.
Princeton subject headings:
Business--History--20th century--Chronology.
Commerce--History--20th century--Chronology.
Economic history--20th century--Chronology.