Roberts J, Price J, Nelson LM, Burchinal M, Hennon E, Barnes B. Receptive vocabulary, expressive vocabulary, and speech production of boys with fragile X syndrome in comparison to boys with Down syndrome. Am J Ment Retard. 2007 May 1;112:177-93.
Rothman KJ, Cann CI, Flanders D, Fried MP. Epidemiology of laryngeal cancer. Epidemiol Rev. 1980;2(1):195-205.