1. Chetyrkin K. G. andTkachov F. V.,Nucl. Phys. B,192 (1981) 159;Tkachov F. V.,Phys. Lett. B,100 (1981) 65. The method was extended to the massive case byGray N.,Broadhurst D. J.,Grafe W. andSchilcher K.,Z. Phys. C,48 (1990) 673.
2. Laporta S. andRemiddi E.,Acta Phys. Pol. B,28 (1997) 959.
3. See, for instance, eq. (B.1) ofBöhm, Spiesberger H. andHollik W.,Fortschr. Phys.,34 (1986) 687. A former investigation of the differential properties of the Feynman graph amplitudes can be found inde Alfaro V.,Jaksic B. andRegge T.,Differential properties of Feynman amplitudes, inHigh Energy Physics of Elementary Particles (IAEA, Vienna) 1965, p. 263.