Hough, B. O. (1920). Ocean traffic and trade. Lasalle Extension University.
Lua i Stíl Chicago (17ú heag.)Hough, Benjamin Olney. Ocean Traffic and Trade. Chicago: Lasalle Extension University, 1920.
Lua MLA (8ú heag.)Hough, Benjamin Olney. Ocean Traffic and Trade. Lasalle Extension University, 1920.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.