The FF package has been written by Geert Jan van Oldenborgh. It is distributed via the FORM site, because orginally FORM was designed as the core of an automatic system for calculating reactions at the tree and one loop level.
The package is considered a standard in the field of one loop integration. Even when it isn't used directly as part of a calculation, people use it to check their integrals. The great advantage of the system is that it handles cases with many mass scales, and it gives an estimate of the error due to numerical cancellations.
For more information about the methods used, please consult the paper
"New Algorithms For One Loop Integrals."
G.J. van Oldenborgh, J.A.M. Vermaseren (NIKHEF, Amsterdam).
Published in Z.Phys.C46:425-438,1990.
The files are:
| ff.tar.gz | The FF package. |
| ffmanual.ps.gz | The FF manual in postscript and gzipped. |
| ffmanual.pdf | The FF manual in .pdf format. |
| README | The (old) readme file. |