STEELE, H. (1998). ECOLOGY AND THE ENVIRONMENT. TIME LIFE PUBLICATIONS.
Lua i Stíl Chicago (17ú heag.)STEELE, HOPE. ECOLOGY AND THE ENVIRONMENT. ASIA: TIME LIFE PUBLICATIONS, 1998.
Lua MLA (9ú heag.)STEELE, HOPE. ECOLOGY AND THE ENVIRONMENT. TIME LIFE PUBLICATIONS, 1998.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.