1. Guidelines on the Provision of Manual Wheelchairs in Less Resourced Settings,2008
2. Use of wheelchairs and other mobility support devices;Shields;Health Rep.,2004
3. U.S. Disability Statistics and Information
http://www.disabled-world.com/disability/statistics/info.php
4. Wheeled Mobility Demographics;Flagg,2009
5. The Social Implications of Increases in Wheelchair Use;Sapey,2004