Holbrook, D. (1961). English for maturity. Univ. Press.
Lua i Stíl Chicago (17ú heag.)Holbrook, David. English for Maturity. Cambridge: Univ. Press, 1961.
Lua MLA (9ú heag.)Holbrook, David. English for Maturity. Univ. Press, 1961.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.