Principles of Compiler Design, by Alfred Aho and Jeffrey Ullman, is a classic textbook on compilers for computer programming languages. Both of the authors won the 2020 Turing Award for their work on compilers.
It is often called the "green dragon book" and its cover depicts a knight and a dragon in battle; the dragon is green, and labeled "Complexity of Compiler Design", while the knight wields a lance and a shield labeled "LALR parser generator" and "Syntax Directed Translation" respectively, and rides a horse labeled "Data Flow Analysis". The book may be called the "green dragon book" to distinguish it from its successor, Aho, Sethi and Ullman's Compilers: Principles, Techniques, and Tools, which is the "red dragon book".