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Mathematics This article is within the scope of WikiProject Mathematics, a collaborative effort to improve the coverage of mathematics on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.MathematicsWikipedia:WikiProject MathematicsTemplate:WikiProject Mathematicsmathematics articles ??? This article has not yet received a rating on the project's priority scale.

A bot has quoted the identity of the content of this stub with a paragraph in [1]. In fact, it appears that this page is an automatic copy of an old version of Associative property, in which all the formulas are lacking. This is thus not a copyvio, and I'll remove the tag. D.Lazard ( talk) 22:30, 17 February 2013 (UTC) reply