Allen, W. P. (1943). Some notes on the old fortifications of Drogheda.
Lua i Stíl Chicago (17ú heag.)Allen, W. P. Some Notes on the Old Fortifications of Drogheda. 1943.
Lua MLA (9ú heag.)Allen, W. P. Some Notes on the Old Fortifications of Drogheda. 1943.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.
