Veryard, R. (1991). The Economics of Information Systems and Software. ELSEVIER.
Lua i Stíl Chicago (17ú heag.)Veryard, Richard. The Economics of Information Systems and Software. ELSEVIER, 1991.
Lua MLA (8ú heag.)Veryard, Richard. The Economics of Information Systems and Software. ELSEVIER, 1991.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.