Columbia subject headings:
Harvard subject headings:
Baby foods industry--United States--Periodicals.
Baked products industry--United States--Periodicals.
Battery industry--United States--Periodicals.
Feed industry--United States--Periodicals.
Flour industry--United States--Periodicals.
Food industry and trade--United States--Periodicals
Ralston Purina Company--Periodicals.
Princeton subject headings:
Ralston Purina Company--Periodicals.