Dunbar, D., Bern, Z., Bjerrum-Bohr, N., Dunbar, D., & Ita, H. (2006). Recursive Approach to One-loop QCD Matrix Elements. Nuclear Physics B - Proceedings Supplements, 157(1), pp. 120-124. doi:10.1016/j.nuclphysbps.2006.03.041

Dunbar, David, Z. Bern, N.E.J Bjerrum-Bohr, D.C Dunbar, and H. Ita. "Recursive Approach to One-loop QCD Matrix Elements." Nuclear Physics B - Proceedings Supplements 157, no. 1 (2006): 120-124.

Dunbar, David, et al. "Recursive Approach to One-loop QCD Matrix Elements." Nuclear Physics B - Proceedings Supplements 157.1 (2006): 120-124.