Answer:
He alludes to revered texts like the Declaration of Independence, the Bible, and the Gettysburg Address.
Step-by-step explanation:
One of the methods that Dr. King employs to establish his authority and credibility is referring to various well-known and respected documents such as the Declaration of Independence, the Bible, and the Gettysburg Address. Dr. King wants to show to the listeners that the ideas that he is proposing are not new or unusual. In fact, the values of liberty, equality and brotherhood have already been discussed by people with more authority or knowledge than him. His aim is only to reconcile what Americans believe their country is like to what their country actually is.