du Toit, C. M. (1990). Fundamental Business Economics (Second Edition). ELSEVIER.
Lua i Stíl Chicago (17ú heag.)du Toit, C M. Fundamental Business Economics (Second Edition). ELSEVIER, 1990.
Lua MLA (8ú heag.)du Toit, C M. Fundamental Business Economics (Second Edition). ELSEVIER, 1990.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.