APA (7th ed.) Citation

Clements, W. H. (2019). Britain's island fortresses. Pen & Sword Military.

Chicago Style (17th ed.) Citation

Clements, W. H. Britain's Island Fortresses. Barnsley, South Yorkshire, UK: Pen & Sword Military, 2019.

MLA (9th ed.) Citation

Clements, W. H. Britain's Island Fortresses. Pen & Sword Military, 2019.