Shorthand for [BOOK Structure and Interpretation of Computer Programs].
This book is one of a small handful commonly referenced when someone asks for a [Scheme] reference book. Beyond that it is a very good introduction into computational concepts in general.
It's also a classic of language theory, quite apparent from its use
of Scheme for exposition; in fact, [CL] hears more recommendations of
it as a tutorial on programming principles than for Scheme.
For the latter role, the usual candidates are '''The Little Schemer''',
...