Can stackoverflow recommend some books on language VMs?
I'm looking for books that cover topics involving dynamic (i.e. python, ruby, etc.) virtual machines, as well as VMs for non-dynamic (i.e. java, CLR) languages. 

Specifically, concepts, challenges, optimizations, etc. 
Can stackoverflow recommend some books on language VMs?
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I'm looking for books that cover topics involving dynamic (i.e. python, ruby, etc.) virtual machines, as well as VMs for non-dynamic (i.e. java, CLR) languages. 

Specifically, concepts, challenges, optimizations, etc. 