Hewlett S A. (2007). Off Ramps and On Ramps. Harvard Bus. School Press.
Lua i Stíl Chicago (17ú heag.)Hewlett S A. Off Ramps and On Ramps. Boston: Harvard Bus. School Press, 2007.
Lua MLA (9ú heag.)Hewlett S A. Off Ramps and On Ramps. Harvard Bus. School Press, 2007.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.