Chisholm, G. G. (1937). Chisholm's handbook of commercial geography. Longmans.
Lua i Stíl Chicago (17ú heag.)Chisholm, George Goudie. Chisholm's Handbook of Commercial Geography. London: Longmans, 1937.
Lua MLA (9ú heag.)Chisholm, George Goudie. Chisholm's Handbook of Commercial Geography. Longmans, 1937.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.