Columbia subject headings:
Agriculture--China--History.
Agriculture--Technology transfer--China--History.
Agriculture--Technology transfer--United States--History.
Agriculture--United States--History.
Agriculturists--United States--History.
Harvard subject headings:
Agriculture--China--History
Agriculture--Technology transfer--China--History.
Agriculture--Technology transfer--United States--History.
Agriculture--United States--History
Agriculturists--United States--History.
Princeton subject headings:
Agriculture--China--History.
Agriculture--China--Technology transfer--History.
Agriculture--United States--History.
Agriculture--United States--Technology transfer--History.
Agriculturists--United States--History.