Easley, J. A. J., Gelder, H. M., & Golden, W. M. (1966). A plato program for instruction and data collection in mathematical problem solving (Reprint.). University of Illinois.
Chicago-viite (17. p.)Easley, J. A. Jr, H. M. Gelder, ja W. M. Golden. A Plato Program for Instruction and Data Collection in Mathematical Problem Solving. Reprint. Urbana, Ill: University of Illinois, 1966.
MLA-viite (9. p.)Easley, J. A. Jr, et al. A Plato Program for Instruction and Data Collection in Mathematical Problem Solving. Reprint. University of Illinois, 1966.
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