Télécomunications / Albert Sorel, Gérard Bauer [et] Roger Michael; Pointes-sèches originales de René Demeurisse
100 avarias TV e a maneira prática de as detectar / Pierre Duranton; Conceição Jardim, Eduardo Lúcio Nogueira
Submarine cable laying and repairing / H. D. Wilkinson
The creed relay : instruction booklet No. 36 / Creed & Co. Ltd.