BLUEBIRD BOOKS. (2001). CHILDREN'S REFERENCE: THE UNIVERSE. BLUEBIRD BOOKS.
Lua i Stíl Chicago (17ú heag.)BLUEBIRD BOOKS. CHILDREN'S REFERENCE: THE UNIVERSE. NEW DELHI: BLUEBIRD BOOKS, 2001.
Lua MLA (9ú heag.)BLUEBIRD BOOKS. CHILDREN'S REFERENCE: THE UNIVERSE. BLUEBIRD BOOKS, 2001.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.