RT Journal Article SR Electronic T1 Commentary on “Association of ground hardness with injuries in rugby union” JF British Journal of Sports Medicine JO Br J Sports Med FD BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine SP 587 OP 587 VO 41 IS 9 A1 Orchard, John W YR 2007 UL http://bjsm.bmj.com/content/41/9/587.abstract AB