Columbia subject headings:
Harvard subject headings:
Cell phones--Germany.
Digital media--Social aspects--Germany.
Internet and children--Germany.
Internet and teenagers--Germany.
Technology and children--Germany.
Wireless Internet--Germany.
Princeton subject headings:
Cell phones--Germany.
Digital media--Social aspects--Germany.
Internet and children--Germany.
Internet and teenagers--Germany.
Technology and children--Germany.
Wireless Internet--Germany.