C# Language Specification
The C# Language Specification is the definitive source for C# syntax and usage. This spec contains detailed information about all aspects of the language, including many points that the documentation for Visual C# doesn't cover.
You can download this spec from the Microsoft Developer Network (MSDN). If you've installed Visual Studio 2013, you can also find the spec on your computer in the Program Files (x86)/Microsoft Visual Studio 12.0/VC#/Specifications/1033 folder. However, installations of Visual Studio Express 2013 don't include this file.