National Geographic Manazines 1960.
Lua i Stíl Chicago (17ú heag.)National Geographic Manazines 1960.
Lua MLA (9ú heag.)National Geographic Manazines 1960.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.
Lua APA (7ú heag.)