Question: Kris Kristofferson, whose songs had been featured on Joan Baez' 1973 compilation "Hits: Greatest and Others," has also been in what music supergroup was with artists Waylon Jennings, Willie Nelson, and Johnny Cash? 
Sentence (from "Hits: Greatest and Others"): Hits: Greatest and Others was a 1973 compilation Vanguard put together at the end of Joan Baez' association with their label.
Relevant evidence: Yes