Duncan, R. (1992). Agricultural Futures and Options. ELSEVIER.
Lua i Stíl Chicago (17ú heag.)Duncan, Richard. Agricultural Futures and Options. ELSEVIER, 1992.
Lua MLA (8ú heag.)Duncan, Richard. Agricultural Futures and Options. ELSEVIER, 1992.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.