Columbia subject headings:
Harvard subject headings:
Mass media and public opinion--Europe--Congresses.
Mass media and public opinion--Germany--Congresses.
Mass media and public opinion--United States--Congresses.
Mass media--Europe--Congresses.
Mass media--Germany--Congresses.
Mass media--United States--Congresses.
Princeton subject headings:
Mass media and public opinion--Germany--Congresses.
Mass media--Europe--Congresses.
Mass media--Germany--Congresses.