Version 1.0 was released in October 1997. It worked on He-RBS data and single spectra only.
Version 2.1 was released in April 1998. It works on RBS and ERDA data, for any incident ion. Non-Rutherford cross sections can be easily added. NDF v2.1 can fit simultaneously up to 10 spectra collected from the same sample
Both of these codes are now obsolete and unsupported.
Any users who have licenced them from us should realise that their licences
have expired and that they should now obtain the new version.