These are the required on the paper and fix the attach solution as per Professor comment.
In terms of edits to the paper, you had multiple mentions of Dubuffet establishing , so I might take one or two of them out. I'd also add more citations where you state a fact or quote someone directly - for example, the line "He was also known as Le Douanier, a humorous description of his occupation as a toll collector" comes directly from his Wikipedia page and therefore needs to be in quotation marks and cited.
I have two things you might want to go back and edit. First in the Dubuffet section there are dates that I don't think line up. Specifically look at your mention of " interest growing in the 90's" what 90's do you mean 1890's or 1990's. In general look at your categorization of artists and the period in which they made art. The second is the beginning of the Art Brut section I think there is a name missing there, other then those quick fixes you did good work.