1. The Dynamics of Audience Fragmentation: Public Attention in an Age of Digital Media
2. Christopher H. Sterling and John Michael Kittross,Stay Tuned: A History of American Broadcasting(Mahwah, N.J.: Erlbaum, 2002), 475.
3. Erik Barnouw,Tube of Plenty: The Evolution of American Television(New York: Oxford University Press, 1975), 260.