Expert .NET 2.0 IL Assembler
If you want to know how .Net Framework works internally then there is very good book by Serge Lidin - Expert .NET 2.0 IL Assembler. Serge Lidin is author of IL Assembler, IL Disassembler. He is also one of those guys who wrote IL Assembler language specification. So I think he knows the topic very well.
NB! This blog is moved to gunnarpeipman.com
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