books.google.com - This is a comprehensive account of the semantics and the implementation of the whole Lisp family of languages, namely Lisp, Scheme and related dialects. It describes 11 interpreters and 2 compilers, including very recent techniques of interpretation and compilation. The book is in two parts. The first...http://books.google.com/books/about/Lisp_in_Small_Pieces.html?id=81mFK8pqh5EC&utm_source=gb-gplus-shareLisp in Small Pieces