Keefer, L. E. (1966). Urban travel patterns for airports, shopping centers, and industrial plants. Highway Research Board, Division of Engineering, National Research Council, National Academy of Sciences.
Lua i Stíl Chicago (17ú heag.)Keefer, Louis E. Urban Travel Patterns for Airports, Shopping Centers, and Industrial Plants. Washington, D.C: Highway Research Board, Division of Engineering, National Research Council, National Academy of Sciences, 1966.
Lua MLA (9ú heag.)Keefer, Louis E. Urban Travel Patterns for Airports, Shopping Centers, and Industrial Plants. Highway Research Board, Division of Engineering, National Research Council, National Academy of Sciences, 1966.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.