MacTutor History of Mathematics: Jules Henri Poincaré  
   Biography, bibliography and poster.
   http://www-gap.dcs.st-and.ac.uk/~history/Mathematicians/Poincare.html

World of Scientific Biography: Poincaré, Henri  
   Concise biography with links to related topics.
   http://scienceworld.wolfram.com/biography/Poincare.html

Henri Poincare  
   Concise biography noting this thinker's seminal importance for chaos theory.
   http://www-chaos.umd.edu/misc/poincare.html

Two Philosophical Mistakes in Poincaré  
   Essay Kelley L. Ross of the Friesian School.
   http://www.friesian.com/poincare.htm

The Relativity of Space  
   Full text of Poincare's 1897 popular explanation of his conception of space.
   http://www.marxists.org/reference/subject/philosophy/works/fr/poincare.htm

Henri Poincaré  
   Short article on this thinker's mathematical legacy.
   http://www.usna.edu/Users/math/meh/poincare.html

Biography.com: Poincaré, Henri  
   A paragraph noting his chief accomplishments.
   http://search.biography.com/print_record.pl?id=6370

Science and Hypothesis  
   Full online text of this Poincare work, as published in English in 1905.
   http://spartan.ac.brocku.ca/~lward/Poincare/Poincare_1905_toc.html

PlanetMath: Poincare, Jules Henri  
   Detailed biographical article, with a mathematical emphasis.
   http://planetmath.org/encyclopedia/JulesHenriPoincare.html

Jules Henri Poincaré  
   Scholarly study of his life and thought by Mauro Murzi. From the Internet Encyclopedia of Philosophy.
   http://www.iep.utm.edu/p/poincare.htm