Special thanks to:
Bill Malon, who kindly sent me the results of 1876-1985 USA National Championships from the book he co-wrote with Ian Buchanan.
Hall Bateman, who helped me in creating the Search Engine and populating it with more than 15,000
American Athletes Profiles.
For the USA Olympic Trials, I covered the final results only. For more information, I recommend you refer to the excellent book,
"The History of the US Olympic Trials," by Richard Hymans.
I used "The Progression of the American National Record" book, published by Scott Davis, Don Potts and Dave Carey as main source for USA Record Progression.