Man Flies by Nancy Winters, 1997, ISBN 0 7475 3596 5
One of the best recent books about Santos-Dumont's life and aeronautical exploits, with some marvellous photographs:
Devotees of the Wright Brothers are warned that they may find some of her claims and views to be rather over-the-top!
For a good general discussion of the claims made for Santos-Dumont see -
http://invention.psychology.msstate.edu/i/Santos-Dumont/Santos-Dumont.html