Não informado. (1978). Mineral Commodity Summaries. Bureau of Mines.
Lua i Stíl Chicago (17ú heag.)Não informado. Mineral Commodity Summaries. Washington: Bureau of Mines, 1978.
Lua MLA (8ú heag.)Não informado. Mineral Commodity Summaries. Bureau of Mines, 1978.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.