Coyle, R. E. (1972). Surveillance from the seas.
Lua i Stíl Chicago (17ú heag.)Coyle, Robert E. Surveillance from the Seas. 1972.
Lua MLA (8ú heag.)Coyle, Robert E. Surveillance from the Seas. 1972.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.