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Lua i Stíl Chicago (17ú heag.)Coal: The Other Energy [kasetvideo]. Washington, D C : National Audio Visual Center, 1978.
Lua MLA (9ú heag.)Coal: The Other Energy [kasetvideo]. Washington, D C : National Audio Visual Center, 1978.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.