Fries, C. (1945). Teaching and learning english as a foreing languaje. University of Michigan.
Lua i Stíl Chicago (17ú heag.)Fries, Charles. Teaching and Learning English as a Foreing Languaje. Ann Arbor: University of Michigan, 1945.
Lua MLA (9ú heag.)Fries, Charles. Teaching and Learning English as a Foreing Languaje. University of Michigan, 1945.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.