Essays / Literary tools analysis MLK "I Have a Dream." - great speeches [7]

I am working on a very large piece considering many great speeches, comparing and analyzing the Literary tools used in each such as : Literal Imagery, Figurative Imagery, Allusion, and Repetition.

Anyone have on old essay or analysis of MLK's "I have a Dream" speech I can look at, or know where to get some good resources?

THNX