http://www.netlib.org/utk/people/JackDongarra/la-sw.html

http://en.wikipedia.org/wiki/Sparse_matrix

http://docs.scipy.org/doc/scipy/reference/sparse.html

http://eigen.tuxfamily.org/dox/TutorialSparse.html

http://www.mathworks.com/help/matlab/ref/sparse.html

http://www.math.mtu.edu/~msgocken/intro/node18.html

http://www.cise.ufl.edu/research/sparse/matrices/

http://www.boost.org/doc/libs/1_53_0/libs/numeric/ublas/doc/matrix_sparse.htm