Literature

C#

Tutorials

An introduction to C# can be found here (in German)

Books

A C# book that quite a few of us in the OpenPetra team find very helpful is 'Illustrated C# 2012' by Daniel Solis, from Apress (750 pages) - available as a book or as an e-book. It is not only for C# beginners (though it will be very good for those), but it is an excellent reference as well. Several of us come back to it from time to time as its explanations are easy to follow, to the point, concise, in-depth, and – as the title implies – often well illustrated.

NUnit

An introduction to NUnit-Testing can be found here