RT Journal Article SR Electronic T1 General practitioner knowledge of prohibited substances in sport. 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 259 OP 259 DO 10.1136/bjsm.31.3.259-b VO 31 IS 3 A1 A D Webborn YR 1997 UL http://bjsm.bmj.com/content/31/3/259.3.abstract AB