Locklin, D. P. (1938). Economics of transportation (Rev. ed.). Business publications, inc..
Lua i Stíl Chicago (17ú heag.)Locklin, D. Philip. Economics of Transportation. Rev. ed. Chicago: Business publications, inc., 1938.
Lua MLA (8ú heag.)Locklin, D. Philip. Economics of Transportation. Rev. ed. Business publications, inc., 1938.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.