Timmers, P. (1999). Electronic Commerce. John Wiley & Sons.
Lua i Stíl Chicago (17ú heag.)Timmers, Paul. Electronic Commerce. New York: John Wiley & Sons, 1999.
Lua MLA (9ú heag.)Timmers, Paul. Electronic Commerce. John Wiley & Sons, 1999.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.