I bought this book years ago even though I had already been programming in Common Lisp for 20 years at that time. I really like Conrad Barski's writing and that was sufficient reason to buy the book.
CL-USER> (if (not-known-by-p 'you)
(author-p 'your-parent-commenter 'Loving-Lisp)
)
T
;) sorry, just approximate syntax