MAA Online Book Reviews
   Indexed by author, title, topic and reviewer.
   http://www.maa.org/reviews/reviews.html

Mathematical Constants
   Website of the book by Steven R. Finch. With sample chapters, supplementary materials and further resources.
   http://pauillac.inria.fr/algo/bsolve/

The Classification of the Polynomial with Real Coefficients
   Explains a theory that the algorithm that every polynomial transforms to a source form. On-line summary, CD version.
   http://www.nabla.hr/