The participation in a software project may be due to a variety of activities, including creation of code, debugging, creation of description, ruling the team etc.
For legal reasons we mention here that some of us were in a shorter term than indicated active with the software itself but rather worked - within the project - on description etc.
We indicate the period of activity if it is not continously. It is not easy to reasonably date the begin of the project. A bit arbitrarily, one may choose the first paper by A. Akhundov, D. Bardin, T. Riemann on "Hunting the hidden standard Higgs", Phys.Lett. B166 (1986) 111, submitted in 1985. What was programmed for this article, became later the standard model library of zfitter, now zfitter/dizet.