Saeid Haghjoo and  Ebrahim Reyhani and  Fahimeh Kolahdouz,  Evaluating the Understanding of the University Students (Basic Sciences and Engineering) about the Numerical Representation of the Average Rate of Change.   journal   = {International Journal of Educational and Pedagogical Sciences}, [online]. World Academy of Science, Engineering and Technology.
    January 2020, vol. 158(2). 111 - 121
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