The sources cited in this work are as follows:
De Fleur, Melvin (1966), Theories of Mass Communication, New York: McKay Company.
Katz, Elihu et al (1974), "Utilization of Mass Communication," in The Uses of Mass Communication, Jay G. Blumler and Elihu Katz, eds., Beverly Hills, CA: Sage Publications, 19-32.
Katz, Elihu and Paul Lazarsfeld (1955), Personal Influence, New York: The Free Press.
Lazarsfeld, Paul et al (1968), The People's Choice, New York: Columbia University Press.
Lazarsfeld, Paul and Herbert Menzel (1974), "Mass Media and Personal Influence, " in The Science of Human Communication, Schramm, ed., 94-115.
Littlejohn, Stephen W (1989), Theories of Human Communication, Belmont, CA: Wadsworth Publishing.
Watson, James and Anne Hill (1997), A Dictionary of Communications Studies, New York: Arnold Publishing.
Wright, Charles R (1974), "Functional Analysis and Mass Communication Revisited," in The Uses of Mass Communication, Jay G. Blumler and Elihu Katz, eds., Beverly Hills. CA: Sage Publications,197-212.
Also, these internet sites were also very helpful:
http://.seas.upenn.edu/~mengwong/comm125.html
This site has some good summary information about communication theories in general, and it originates from the University of Pennsylvania.
http://www.udel.edu/johnc/courses/grad/com670.html
This is a site from the University of Delaware, which links to the syllabus for a graduate class in communication theory. There are many good leads for research sources throughout the syllabus.
http://uts.cc.utexas.edu/~tecas/Syl382JFall1997.html
Here you will find the syllabus for the graduate course that this site was created for. There are many articles about functional theory, as well as articles discussing other communications theories, included as pdf files on this site. All you need is a copy of Adobe Acrobat reader to download them.
To find out more about this site and its author, click here.
