RT Journal Article SR Electronic T1 Towards an operational definition of sports concussion: identifying a limitation in the 2012 Zurich consensus statement and suggesting solutions 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 1589 OP 1591 DO 10.1136/bjsports-2014-094112 VO 48 IS 22 A1 Kenneth Lincoln Quarrie A1 Ian Robert Murphy YR 2014 UL http://bjsm.bmj.com/content/48/22/1589.abstract AB