Formally, an [[iterated function]] system is a finite set of [[contraction mapping]]s on a [[complete metric space]].<ref>Michael Barnsley (1988). ''Fractals Everywhere'', p.82. Academic Press, Inc. {{ISBN|9780120790623}}.</ref> Symbolically,
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Formally, an [[iterated function]] system is a finite set of [[contraction mapping]]s on a [[complete metric space]].<ref>Michael Barnsley (1988). ''Fractals Everywhere'', p.82. Academic Press, Inc {{cite book |isbn=9780120790623}}</ref> Symbolically,