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