Turvey, R. (1980). Demand and supply. Allen & Unwin.
Lua i Stíl Chicago (17ú heag.)Turvey, Ralph. Demand and Supply. London: Allen & Unwin, 1980.
Lua MLA (9ú heag.)Turvey, Ralph. Demand and Supply. Allen & Unwin, 1980.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.