Premise: 50th Birthday Celebration Volume 9 (also referred to as The Classic Guide to Strategy Volume 3: The Fire Book) is a live album by John Zorn featuring a solo performance at Tonic in September 2003 that was part of his month-long 50th Birthday Celebration concert series. It is a continuation of his solo work documented on "The Classic Guide to Strategy Volumes 1 & 2".
Hypothesis: "The Classic Guide to Strategy Volumes 1 & 2" is popular in Portugal.