* [Concepts & Applications of Inferential Statistics](http://vassarstats.net/textbook/)
* [Differential Equations](http://tutorial.math.lamar.edu/pdf/DE/DE_Complete.pdf) - Paul Dawkins
* [Differential Equations](http://tutorial.math.lamar.edu/pdf/DE/DE_Complete.pdf) - Paul Dawkins
* [Elementary Differential Equations](http://ramanujan.math.trinity.edu/wtrench/texts/TRENCH_DIFF_EQNS_I.PDF) - William F. Trench
* [Essentials of Metaheuristics](http://cs.gmu.edu/~sean/book/metaheuristics/) by Sean Luke
* [Introduction to Probability](http://www.dartmouth.edu/~chance/teaching_aids/books_articles/probability_book/book.html) - Charles M. Grinstead and J. Laurie Snell
@ -671,6 +673,16 @@
* [Using C on the UNIX System - David A. Curry](http://www.bitsinthewind.com/about-dac/publications/using-c-on-the-unix-system)
* [Fundamentals of Computer Programming with C#](http://www.introprogramming.info/english-intro-csharp-book/read-online/) - Svetlin Nakov
* [HTTP Programming Recipes for C# Bots](http://www.heatonresearch.com/articles/series/20)
* [Game Creation with XNA](http://en.wikibooks.org/wiki/Game_Creation_with_XNA)
* [Moving to Microsoft Visual Studio 2010](http://blogs.msdn.com/b/microsoft_press/archive/2010/09/13/free-ebook-moving-to-microsoft-visual-studio-2010.aspx)
* [.NET for Visual FoxPro Developers](http://foxcentral.net/microsoft/NETforVFPDevelopers.htm)
* [.NET Performance Testing and Optimization - The Complete Guide](http://download.red-gate.com/ebooks/DotNet/Perf_Test_and_opt_eBook.zip) *(RedGate, By Paul Glavich and Chris Farrell)*
* [Practical Performance Profiling: Improving the efficiency of .NET code](http://www.red-gate.com/products/dotnet-development/ants-performance-profiler/entrypage/practical-performance-profiling) *(RedGate, By Jean-Philippe Gouigoux)*
* [Threading in C#](http://www.albahari.com/threading/)
* [Visual Studio Tips and Tricks](http://www.infoq.com/minibooks/vsnettt) (VS 2003-2005 only)
* [Visual Studio .NET Tips and Tricks](http://www.infoq.com/minibooks/vsnettt) (VS 2003-2005 only)
* [Under the Hood of .NET Memory Management](http://download.red-gate.com/ebooks/DotNet/Under_the_Hood_of_.NET_Management.pdf) (PDF) *(RedGate, By Chris Farrell and Nick Harrison)*