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Efficiency and productivity growth comparisons of European and US air carriers : a first look at the data
Good, David H., (1992)
Do energy prices induce progress in energy-related technology? : An empirical study
Schmitz, Simon, (2001)
Productive efficiency and contract management : some evidence from public transit agencies
The relative efficiency and rate of technology adoption of Asian and North American airline firms
Ahn, Seung Chan, (1999)