[kjak]

LoL's author has a collection of references at http://letoverlambda.com/references.lisp

Many of the references are not for learning CL, but are interesting reads (such as Henry Baker's papers).

Also there are references to particular pages of books (noting something important, interesting or funny):

   (cltl2 :a guy-steele :y 1990
     :n "Common Lisp the Language 2nd Ed.")
   (cltl2-p153 :i "Chevrolet!")
   (cltl2-p260
     :i "Can't define compiler macros over CL forms")

etc.