Conversation so far:
What happened in the late 1930s for Duke Ellington?
From 1936, Ellington began to make recordings with smaller groups drawn from his then-15-man orchestra and he composed pieces intended to feature a specific instrumentalist.
Who was a part of the group Duke Ellington worked with in the later 1930s when Ellington was more focused on composing to feature a specific instrumentalist?
Billy Strayhorn, originally hired as a lyricist, began his association with Ellington in 1939.
Did Duke Ellington produce any music with Billy Strayhorn?
Three-minute masterpieces on 78 rpm record sides continued to flow from Ellington, Billy Strayhorn, Ellington's son Mercer Ellington, and members of the Orchestra.
Were the songs released from Ellington, Billy Strayhorn and Ellington's son Mercer Ellington successful?
Billy Strayhorn's Take the A Train a hit in 1941, became the band's theme, replacing East St. Louis Toodle-Oo.
Did Duke Ellington produce any other music besides Billy Strayhorn's Take the A Train and East St Louis Toodle-Oo?
An album produced by George Avakian that would become the best-selling LP of Ellington's career.
Are there any other interesting aspects about this article?
Ellington's appearance at the Newport Jazz Festival on July 7, 1956 returned him to wider prominence and introduced him to a new generation of fans, resulted in an album.

Question: who else did he work with?
Self-contained rewrite: Who else did Duke Ellington work with besides George Avakian, Billy Strayhorn, and Mercer Ellington?