1. 1 WJ Cunliffe . Natural history of acne. In:Acne and Related Disorders(Marks R, ed.). London: M. Dunitz, 1989 ; 4, 6 .
2. 3 V Goulden, SM Clark, and WJ Cunliffe . Post-adolescent acne: a review of clinical features . J Am Acad Dermatol1999 (in press).