Johnson, D. A., & Lund, C. H. (1967). Bulletin Board Displays for Mathematics. California: M&T.
Dyfyniad Arddull ChicagoJohnson, Donovan A., và Charles H. Lund. Bulletin Board Displays for Mathematics. California: M&T, 1967.
Dyfyniad MLAJohnson, Donovan A., và Charles H. Lund. Bulletin Board Displays for Mathematics. California: M&T, 1967.
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