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Lua i Stíl Chicago (17ú heag.)ebrary, Inc, agus William S. Carlsen. Watershed Dynamics. Teacher ed. Arlington, Va.: National Science Teachers Association, 2004.
Lua MLA (9ú heag.)ebrary, Inc, agus William S. Carlsen. Watershed Dynamics. Teacher ed. National Science Teachers Association, 2004.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.