Bodie, G. (2010). A Racing Heart, Rattling Knees, and Ruminative Thoughts: Defining, Explaining, and Treating Public Speaking Anxiety, Communication Education, 59(1), 70-105.
Bodie's research study provides a pretty thorough review of public speaking anxiety. You can access the article by going to the MSU library web page and entering your MSU ID and password: Click Here