I was rereading "Out of the tarpit" paper, and by the end of it I noticed they reference a paper from Henry Baker: "Equal rights for functional objects or, the more things change, the more they are the same.". The author's name rang a bell, and I decided to explore a bit more.
So, He's the author of a paper I loved to read 3 months ago or so: Pragmatic Parsing in Common Lisp.
The article is an adaptation of Val Schorre's META-II paper to common lisp, leveraging reader macros to create parsers in very few lines of code.
Reading a bit more, I found this other very enjoyable article: Metacircular Semantics for Common Lisp Special Forms . This one takes the approach of metacircular interpreters to explain the behaviour of some common lisp special forms in terms of other common lisp expressions. I love the bottom up approach, and reminds me of "git from the bottom up", or CTMCP's explanations of the extensions to the Oz language.
He wrote lots of articles related to Lisp to different degrees, but most of them (the ones I skimmed) are written in a very clear language (no pun intended), and quite fun and enlightening reads.