An extension of the secant method of root finding to higher dimensions.
References
Broyden, C. G. ``A Class of Methods for Solving Nonlinear Simultaneous Equations.''
Math. Comput. 19, 577-593, 1965.
Press, W. H.; Flannery, B. P.; Teukolsky, S. A.; and Vetterling, W. T.
Numerical Recipes in FORTRAN: The Art of Scientific Computing, 2nd ed. Cambridge, England:
Cambridge University Press, pp. 382-385, 1992.