Stebbing, L. S. (1939). Thinking to some purpose. Penguin Books.
Lua i Stíl Chicago (17ú heag.)Stebbing, L. Susan. Thinking to Some Purpose. Harmondsworth: Penguin Books, 1939.
Lua MLA (8ú heag.)Stebbing, L. Susan. Thinking to Some Purpose. Penguin Books, 1939.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.