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2. Fault Tree Analysis: An emerging methodology for instructional science
3. H. R. Wulff,Rational Diagnosis and Treatment(2nd ed), Oxford: Basil Blackwell, 1981; T. R. Taylor, ‘Models of the Diagnostic Process’, unpublished PhD thesis, University of Glasgow, 1971.
4. Development of formal hypothesis-testing ability.
5. P. Cutler,Problem Solving in Clinical Medicine: from data to diagnosis, Baltimore: Williams and Wilkins, 1979; N. Deo,Graph Theory Applications to Engineering and Computer Science, Englewood Cliffs, New Jersey: Prentice Hall, 1974.