Heller, R. (2008). Essential Manager`s Manual.
Lua i Stíl Chicago (17ú heag.)Heller, Robert. Essential Manager`s Manual. New Delhi, 2008.
Lua MLA (9ú heag.)Heller, Robert. Essential Manager`s Manual. 2008.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.