7Hmelo, C. E., & Ferrari, M. ( 1997 ). The problem- based Learning tutorial: Cultivating higher order thinking skills. Journal for the Education of the Gifted, Vol. 20(4), p401 - 422.
8Resnick: B. (1987). Education and learning to think. Washington, DC:National Academy Press.
10Savery,J. R. & Duffy,T. M. (1995). Problem-based learning: An instructional model and its constructivist framework. Educational Technology, Sep./Oct. 31 - 38.
