6GiUen T. A brief review of milestones in the global program for the prevention of blindness// Kupfer C, GiUen T. World blindness and its prevention. Volume 4. International agency for the prevention of blindness, 1991 : 375-385.
7Wang LD. China's efforts on the prevention and treatment of blindness.//Pararajaaegaram R, Rao G. World blindness and its prevention. Volume 6. International agency for the prevention of blindness. Hyderabad: Pragati Art Printers,2001:439-447.
