It was one of the most popular album covers EVER at the time.... and I think remains so today historically.
I'm NOT going to look it up, rather take a guess.... but I think Sgt. Pepper's by the Beatles would be the all time most popular album cover? Although, I hear almost as much about their "White Album". And of course there is "Abbey Road".
Personally I love Santana's Abraxs cover. That 'may' be my favorite?
I'm hesitant to google that because I'm SURE what will be listed 'mostly' are the most 'shocking' album covers... which I don't personally think equates to 'best' or most 'artistic'. - JamesJM