Devine, D. F. \. O. (1991). Elementary mathematics for teachers (2.). John Wiley & Sons.
Dyfyniad Arddull ChicagoDevine, Donald F. \ Olson. Elementary Mathematics for Teachers. 2. España: John Wiley & Sons, 1991.
Dyfyniad MLADevine, Donald F. \ Olson. Elementary Mathematics for Teachers. 2. John Wiley & Sons, 1991.
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