20th Century Fortification
| Author | Title | Source |
|---|---|---|
| J E Kaufmann | The Maginot Line: A Basic Primer (0.3MB) Plates (2.9MB) | FORT, Vol 33, 2005, pp34-55 |
| Bill Clements | The Guns of Shetland: The Coast Defence Batteries (0.18MB) |
Casemate, Vol 90, 2011, pp30-32 |