Speakers use oral footnotes in a speech or presentation to establish the credibility of the information presented. The audience should be assured that the information comes from a reliable source which can be looked up later by an interested listener.
Examples:
In a September 2009 speech to Congress, President Obama stated, "It has now been nearly a century since Theodore Roosevelt first called for health care reform. And ever since, nearly every President and Congress, whether Democrat or Republican, has attempted to meet this challenge in some way."
According to a November 2009 Gallup Poll, 38% of ...