NOT EXISTS shouldn't have a column name before it. Remove the a. Artist_id from before the not exists.
I know this is not an answer, but I could not place a table within the comments so I am putting it here.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.