MINPACK

        M. J. D. Powell, A Hybrid Method for Nonlinear Equations.
        Numerical Methods for Nonlinear Algebraic Equations,
        P. Rabinowitz, editor. Gordon and Breach, 1970.

        Jorge J. More, The Levenberg-Marquardt Algorithm, Implementation
        and Theory. Numerical Analysis, G. A. Watson, editor.
        Lecture Notes in Mathematics 630, Springer-Verlag, 1977.

NEWTON

D.C. Sorenson, Newton's Method with a Model Trust Region Modification,
SIAM J Numer Anal 19 (1982) pp 409--426

J.E. Dennos, R.B. Schnabel, Numerical Methods for Unconstrained
Optimization and Nonlinear Equations, Prentice-Hall, 1983 (reprinted
1996, SIAM Press)