The core algorithm of lmfit has been invented by K. Levenberg (1944) and D. W. Marquardt (1963). The seminal FORTRAN implementation of MINPACK is due to J. M. Moré, B. S. Garbow, and K. E. Hillstrom (1980). An automatic translation into C was first published by S. Moshier. The present library lmfit started from a similar automatic translation. With time, every single line was hand edited to convert the code into genuine, readable C. The API was modified; examples, man pages, and build scripts were added. Corrections and refinements were contributed by users (see CHANGELOG).
When using lmfit as a tool in scientific work, no acknowledgement is needed: If fit results are robust, it does not matter by which software they have been obtained. If results are not robust, they should not be published anyway. In methodological publications that describe software interacting with lmfit, the preferred form of citation is:
Joachim Wuttke: lmfit – a C library for Levenberg-Marquardt least-squares minimization and curve fitting. Version […], retrieved on […] from http://apps.jcns.fz-juelich.de/lmfit.