Porteous , I. R. (2001). Geometric differentiation: For the intelligences of curves and surfaces.-2nd ed (2nd ed.). Cambridge University Press.
Čikaški stil citiranjaPorteous , I. R. Geometric Differentiation: For the Intelligences of Curves and Surfaces.-2nd Ed. 2nd ed. Cambridge: Cambridge University Press, 2001.
MLA način citiranjaPorteous , I. R. Geometric Differentiation: For the Intelligences of Curves and Surfaces.-2nd Ed. 2nd ed. Cambridge University Press, 2001.
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