Enciclopédia multimédia verbo [documento electrónico] / Verbo Multimedia
Novo prontuário ortográfico / J. M. de Castro Pinto
OFTEL annual report 1991 : report of the Director General of Telecommunications: for the period 1 January to 31 December 1991 to the Secretary of State for Trade and Industry / ed. OFTEL
OFTEL annual report 1992 : report of the Director General of Telecommunications: for the period 1 January to 31 December 1992 to the Secretary of State for Trade and Industry / ed. OFTEL