Part appears on the verso of trumpet 2 part of Blow by blow. Handwriting and other details have been reported based on the notes of David Berger, Andrew Homzy, Dr. Theodore Hudson, Walter van de Leur, and Dr. Mark Tucker.
There appears to be a number from the Duke Ellington Band Book: 107
Diminuendo in blue is contained in one folder consisting of 1 part in Eb Major concert -- in ink -- in unidentified hand (Whaley?).
Part for trumpet 3. Part appears on the verso of trumpet 2 part of Blow by blow. -- from the Duke Ellington Library.