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Lua i Stíl Chicago (17ú heag.)Walker Sally M. Early Bird Earth Science Glaciers. 2010 2010: Lerner.
Lua MLA (9ú heag.)Walker Sally M. Early Bird Earth Science Glaciers. Lerner.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.