Não informado. (1990). Geo info systems. Advanstar Communications.
Lua i Stíl Chicago (17ú heag.)Não informado. Geo Info Systems. Duluth, Minn: Advanstar Communications, 1990.
Lua MLA (8ú heag.)Não informado. Geo Info Systems. Advanstar Communications, 1990.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.