This guy is located on the back of the Grateful Dead's album Shakedown Street.
Grateful Dead Shakedown Street 1978 Front and Back Covers.
Grateful Dead Workingmans Dead 1970 Front and Back Covers
Good Lovin', Sometime in the 1970s Front Cover Only
Grateful Dead (Live 2 LP set), 1971 Outside and Inside Covers
If you want to learn more about the Grateful Dead, here is the official site.