Suggest adding another non-standard IVT reference 

In addition to the alternative proof link non-standard calculus possibly add refference to the Constructivist analysis article.  There is a is a long section on IVT in that page.  The Constructivist analysis IVT section forward references to this page.  A link to that discussion might be usefull in this article.

However, I believe the that the the discussion of 'classical analysis IVT' on that page is not in close aggrement with this page.

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