Maryland Geological Survey. (1913). Devonian: Plates. Johns Hopkins Press.
Lua i Stíl Chicago (17ú heag.)Maryland Geological Survey. Devonian: Plates. Baltimore: Johns Hopkins Press, 1913.
Lua MLA (8ú heag.)Maryland Geological Survey. Devonian: Plates. Johns Hopkins Press, 1913.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.