World radio TV handbook 2000
Tratado de Roma de 25 de Março de 1957 : que institui a Comunidade Económica Europeia (C.E.E.) / Jorge de Jesus Ferreira Alves
Europe relaunched : truths and illusions on the way to 1992 / Nicholas Colchester; David Buchan
Transmission networking : SONET and the synchronous digital hierarchy / Mike Sexton and Andy Reid