National Council of Teachers of Mathematics. Geometría informal (1a ed., 6a reimpresión.).
Čikaški stil citiranja (17. izdanje)National Council of Teachers of Mathematics. Geometría Informal. 1a ed., 6a reimpresión.
MLA način citiranja (8. izdanje)National Council of Teachers of Mathematics. Geometría Informal. 1a ed., 6a reimpresión.
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