One chapter lays out DenotationalSemantics for the SchemeLanguage. Another discusses the relative merits of single and multiple namespaces for LispLanguages (see SingleNamespaceLisp).
(Note the RecursiveAcronym in the title: Lisp in Small Pieces == L.i.S.P.)
The programs from this book are available from http://www-spi.lip6.fr/~queinnec/WWW/LiSP.html