SMS [documento electrónico] : uma forma diferente de comunicação no Natal / Maria do Carmo Gomes
The expanding digital universe [documento electrónico] : a forecast of worldwide information growth through 2010 / John F. Gantz...[et al.]
Wholesale service structure [documento electrónico] / David James
Rethinking universal service for a next generation network environment [documento electrónico] / Organisation for Economic co-Operation and Development