Wollan, R. &. O. (2013). Selling through someone else. John Wiley.
Lua i Stíl Chicago (17ú heag.)Wollan, Robert & Others. Selling Through Someone Else. New Jersey: John Wiley, 2013.
Lua MLA (9ú heag.)Wollan, Robert & Others. Selling Through Someone Else. John Wiley, 2013.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.