09. Congdon N, Zheng M, Sharma A, et al. Prevalence and determinants of spectacle nonwear among rural chinese secondary schoolchildren: The xichang pediatric refractive error study report 3. Arch.Ophthalmol. 2008;126:1717-1723.

09. Congdon N, Zheng M, Sharma A, et al. Prevalence and determinants of spectacle nonwear among rural chinese secondary schoolchildren: The xichang pediatric refractive error study report 3. Arch.Ophthalmol. 2008;126:1717-1723.