ALLEN, W. S. (1974). Living english structure: Key to the exercises. Longman.
Lua i Stíl Chicago (17ú heag.)ALLEN, W. Stannard. Living English Structure: Key to the Exercises. London: Longman, 1974.
Lua MLA (9ú heag.)ALLEN, W. Stannard. Living English Structure: Key to the Exercises. Longman, 1974.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.