Não informado. (2007). Marketing letters. Kluwer Academic Publishers.
Lua i Stíl Chicago (17ú heag.)Não informado. Marketing Letters. Dordrecht, Holanda: Kluwer Academic Publishers, 2007.
Lua MLA (8ú heag.)Não informado. Marketing Letters. Kluwer Academic Publishers, 2007.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.