Casgliadau Arlein
Amgueddfa Cymru
Chwilio Uwch
Post Office Green Paper
Post Office Green Paper No.26 - "Voice-Frequency Telegraphy". 32 pages with black and white photos and diagrams.
Pwnc
Diwydiant
Rhif yr Eitem
91.46I/15
Derbyniad
Collected officially, 11/9/1991
Mesuriadau
Meithder
(mm): 245
Lled
(mm): 186
Deunydd
papur
metel
Lleoliad
In store
Nid yw sylwadau ar gael ar hyn o bryd. Ymddiheuriadau am yr anghyfleustra.