The Anglo Portuguese Telephone C.º Ltd : subsídios para a sua história / Introd. Luiz Teixeira : [texto de Eng.º Armando Ferreira ... et al.]; The Anglo Portuguese Telephone, Co. Ltd.
La electicidad y sus fenómenos : (terminologia eléctrica) / Santiago Andreu
Les télécommunications / Bruno Aurelle
Girdle round the earth : the story of cable and wireless and it predecessors to mark the group's jubilee: 1929-1979 / Hugh Barty-King