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The value of time in passenger transportation, the demand for air travel
Gronau, Reuben, (1970)
Middle east-europe and middle east-north America traffic flows
Lefèvre, Gilles, (1979)
Economy and efficiency of international air travel by government officials : Hearings before a subcommittee of the Committee on Government Operations, House of Representatives, Ninety-second Congress, second session
(1972)