1. Allnutt, M. (1990). Personal communication [Army Personnel Research Establishment, Farnborough, UK].
2. Aviation Safety Reporting System. (1990). Foreign language difficulties (Special Request No. 1815 ). Mountain View, CA: Battelle Columbus, Division ASRS Office.
3. Baker, S. (1989). Personal communication [British Civil Aviation Authority, Farnborough,UK].
4. Baldwin, R. (1990). Personal communication [EUROCONTROL Institute of Air Navigation Services].
5. Booher, H. R., & Rouse, W. B. (1990). MANPRINT as the competitive edge. In H. R. Booher (Ed), MANPRINT: An approach to systems integration. New York: Van Nostrand Reinhold.