Parton-shower uncertainties with Herwig 7: benchmarks at leading order Johannes Bellm, Graeme Nail, Simon Plätzer, Peter Schichtel and Andrzej Siódmok Eur. Phys. J. C, 76 12 (2016) 665 Published online: 02 December 2016 DOI: 10.1140/epjc/s10052-016-4506-x