About Philip J. Corso
The Day After Roswell is a memoir that claims the U.S. government made use of extraterrestrial technology it recovered from the 1947 Roswell incident. It was ghostwritten by William J. Birnes and credited to Philip J. Corso. Published as Corso's tell-all autobiography by Pocket Books in 1997, the book spent three weeks on the New York Times bestseller list and received mixed reviews. Analysts have noted a large number of errors about basic, known facts in the text, as well as chronologically impossible feats the book attributes to Corso. The book has been alleged to be a hoax.
Biography source:
Wikipedia