Goh, D. (1997). Start selling stop order taking. Sterling.
Lua i Stíl Chicago (17ú heag.)Goh, David. Start Selling Stop Order Taking. New Delhi: Sterling, 1997.
Lua MLA (9ú heag.)Goh, David. Start Selling Stop Order Taking. Sterling, 1997.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.