Head Injury in SportBMJ 308:1620-1624, McLatchie,G.&Jennett,B., 1994
Horseback Riding and Head InjuriesCommittee on Sports Medicine and Fitness, Pediatrics 89:5121992., , 1992
Serious Head Injury in SportBMJ 281:789-791, Lindsay,K.W.,et al, 1980