Secretariat (March 30, 1970 – October 4, 1989) was an American Thoroughbred racehorse that in 1973 became the first U.S. Triple Crown champion in 25 years. He set race records in all three events in the Series — the Kentucky Derby (1:59.4), the Preakness Stakes (1:53), and the Belmont Stakes (2:24) — records that still stand today. He is considered to be one of the greatest Thoroughbreds of all time, ranking second behind Man o' War in The Blood-Horse's List of the Top 100 U.S. Racehorses of the 20th Century.

 
http://en.wikipedia.org/wiki/Secretariat_(horse)

Obituary titled 'Pure Heart' written by William Nack for Sports Illustrated. 
http://sportsillustrated.cnn.com/vault/article/magazine/MAG1136808/index.htm

"Secretariat is an elegantly crafted, exhilarating tale of speed and power, grace and greatness, told with such immediacy that the reader is lost in the rush of horses and the clatter and ring of the grandstand."
-- Laura Hillenbrand, author of Seabiscuit.