Columbia subject headings:
Developing countries--Commerce--Econometric models.
Developing countries--Commerce--History--20th century.
Developing countries--Commerce--Mathematical models.
Harvard subject headings:
Developing countries--Commerce--Econometric models.
Developing countries--Commerce--History--20th century.
Developing countries--Commerce--Mathematical models.
Princeton subject headings:
Developing countries--Commerce--Econometric models.
Developing countries--Commerce--History--20th century.
Developing countries--Commerce--Mathematical models.