Common Lisp Implementations: A Survey
common-lisp.net
common-lisp.net
http://www.cs.northwestern.edu/academics/courses/325/reading...
ANSI CL was the first book that helped me enjoy Lisp. My previous books were all vintage "AI" books that were dull. However, one quickly grows out the Graham subset of Common Lisp and ends up using the language to its full potential (i.e. with proper iteration, condition system, object system, exceptions, packages and modules.)
Actually, this book is one that I'd like to keep on the (virtual) back burner. But there is no way I store more paper on my shelves. Fortunately, I bought Practical CL before I set this rule :) But how do I thank PG for On Lisp?