Johnston, B. L., & Richman, F. (1997). Numbers and symmetry: An introduction to algebra. CRC Press.
Dyfyniad Arddull ChicagoJohnston, Bernard L., and Fred Richman. Numbers and Symmetry: An Introduction to Algebra. Boca Raton: CRC Press, 1997.
Dyfyniad MLAJohnston, Bernard L., and Fred Richman. Numbers and Symmetry: An Introduction to Algebra. CRC Press, 1997.
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