Mathematics resources listed

First of all rules taught at the university: Never trust Wikipedia ;-)
It isn't all to bad and not only restricted to Wikipedia in the end, but it contains an important message: Never ever trust what you get told about mathematics!
Or at least not blindly trust it. Everyone can make a mistake and especially in the internet many information are published quiet to fast and seldom are reviewed accordingly.
The same is true for the materials found on this domain as well as for the list below.

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