Bradfield, D. J. (1966). Guide to extension training. Food and Agriculture Organization of the United Nations.
Lua i Stíl Chicago (17ú heag.)Bradfield, D. J. Guide to Extension Training. Rome: Food and Agriculture Organization of the United Nations, 1966.
Lua MLA (8ú heag.)Bradfield, D. J. Guide to Extension Training. Food and Agriculture Organization of the United Nations, 1966.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.