Kann L, Collins J L, Pateman B C, Small M L, Ross J G, Kolbe L J
Division of Adolescent and School Health, Centers for Disease Control and Prevention, Atlanta, GA 30341-3724, USA.
J Sch Health. 1995 Oct;65(8):291-4. doi: 10.1111/j.1746-1561.1995.tb03376.x.