On Computing Certain Elements of the Inverse of a Sparse Matrix
A recursive algorithm for computing the inverse
of a matrix from the LU factors based on relationships 
in Takahashi, et al., is examined.  The formulas for the
algorithm are given; the dependency relationships 
are derived; the computational costs are developed; and some
general comments on application and stability 
are made.
CACM March, 1975
Erisman, E. M.
Tinney, W. F.
