IR singularities in noncommutative perturbative dynamics? J. M. Grimstrup, H. Grosse, L. Popp, V. Putz, M. Schweda, M. Wickenhauser and R. Wulkenhaar Europhys. Lett., 67 2 (2004) 186-190 Published online: 01 July 2004 DOI: 10.1209/epl/i2003-10285-9