Não informado. (1987). Agricultural Administration and Extension. Elsevier Applied Science.
Lua i Stíl Chicago (17ú heag.)Não informado. Agricultural Administration and Extension. Essex, Inglaterra: Elsevier Applied Science, 1987.
Lua MLA (8ú heag.)Não informado. Agricultural Administration and Extension. Elsevier Applied Science, 1987.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.