S. Harper, и P. Green. International Conference on Computers Helping People with Special Needs, стр. 289--296. Germany, OCG Press, (июля 2000)Under the auspices of the UNESCO.
P. Green, и S. Harper. International Conference on Computers Helping People with Special Needs, стр. 281--288. Germany, OCG Press, (июля 2000)Under the auspices of the UNESCO.