Columbia subject headings:
Automatic machinery--United States--Statistics--Periodicals.
Industrial equipment--United States--Statistics--Periodicals.
Manufacturing industries--Technological innovations--United States--Statistics--Periodicals.
Manufacturing processes--United States--Statistics--Periodicals.
Harvard subject headings:
Automatic machinery--United States--Statistics--Periodicals.
Industrial equipment--United States--Statistics--Periodicals.
Manufacturing industries--Technological innovations--United States--Statistics--Periodicals.
Manufacturing processes--United States--Statistics--Periodicals.
Princeton subject headings: