This elegiac farewell to Lester Young was composed by Charles Mingus shortly after Prez’s death, and appeared on his essential Mingus Ah Um album. The musicians:
Charles Mingus, bass
Horace Parlan, piano
Dannie Richmond, drums
John Handy, Booker Ervin, Shafi Kadi, tenor sax
Doesn’t get more mournful or beautiful than this: