Farol, H. F. (1987). A manual 0f effective business correspondence. University Book Supply.
Lua i Stíl Chicago (17ú heag.)Farol, Honesto F. A Manual 0f Effective Business Correspondence. Manila: University Book Supply, 1987.
Lua MLA (9ú heag.)Farol, Honesto F. A Manual 0f Effective Business Correspondence. University Book Supply, 1987.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.