Tull, D. S. A. (1988). Research for Marketing Decisions Green, Paul E. International Book House Pvt. Ltd.
Lua i Stíl Chicago (17ú heag.)Tull, Donalds S; Albaum. Research for Marketing Decisions Green, Paul E. New Delhi: International Book House Pvt. Ltd, 1988.
Lua MLA (9ú heag.)Tull, Donalds S; Albaum. Research for Marketing Decisions Green, Paul E. International Book House Pvt. Ltd, 1988.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.