References

The Levenberg-Marquardt algorithm for nonlinear least squares curve-fitting problems
https://people.duke.edu/~hpgavin/lm.pdf

Methods for non-linear least squares problems
(https://www2.imm.dtu.dk/pubdb/edoc/imm3215.pdf)

minpack.lm
https://github.com/cran/minpack.lm

nlsLM
(https://cran.r-project.org/web/packages/minpack.lm/minpack.lm.pdf)

Numerical Recipes Routines and Examples in Basic, Julein C.Sprott