1. Pedotti A. In: Bougie T, Davies A eds. Wheelchairs: research evaluation and information . Milan: Edizione Pro Juventute , 1986: 5.
2. Dollfus P. In Bougie T, Davies A eds. Wheelchairs: research evaluation and information . Milan: Edizione Pro Juventute , 1986: 37-38.
3. Scottish Home and Health Department/Scottish Health Service Planning Council. The wheelchair service in Scotland. London: HMSO, 1983: 13.