Ormerod, J. (2007). Ballet sisters: The duckling and the swan. Scholastic.
Lua i Stíl Chicago (17ú heag.)Ormerod, Jan. Ballet Sisters: The Duckling and the Swan. New York: Scholastic, 2007.
Lua MLA (8ú heag.)Ormerod, Jan. Ballet Sisters: The Duckling and the Swan. Scholastic, 2007.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.