Columbia subject headings:
Mass media--Social aspects--History--19th century.
Mass media--Technological innovations--History--19th century.
Printing--Social aspects--History--19th century.
Printing--Technological innovations--History--19th century.
Harvard subject headings:
Mass media--Social aspects--History--19th century.
Mass media--Technological innovations--History--19th century.
Printing--Social aspects--History--19th century.
Printing--Technological innovations--History--19th century.
Princeton subject headings:
Mass media--Social aspects--History--19th century.
Mass media--Technological innovations--History--19th century.
Printing--Social aspects--History--19th century.
Printing--Technological innovations--History--19th century.