School Mathematics Study Group. (1968). Puzzle problems and games project: Final report. Leland Stanford Junior University.
Chicago-viite (17. p.)School Mathematics Study Group. Puzzle Problems and Games Project: Final Report. Stanford, CA: Leland Stanford Junior University, 1968.
MLA-viite (9. p.)School Mathematics Study Group. Puzzle Problems and Games Project: Final Report. Leland Stanford Junior University, 1968.
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