Não informado. (1969). Abstracts. Institute of Petroleum.
Lua i Stíl Chicago (17ú heag.)Não informado. Abstracts. London: Institute of Petroleum, 1969.
Lua MLA (8ú heag.)Não informado. Abstracts. Institute of Petroleum, 1969.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.