Dolarhyde goes to the Brooklyn Museum to see the William Blake painting "The Great Red Dragon and the Woman Clothed [in] Sun" he claims to museum staff member Paula Harper he wants to see it for research on a paper he is writing. He says it's "a paper on Butts" to which Paula replies "On William Butts?" which he nods to. She then says "I've never read much on him. You only see him in footnotes as a patron of Blake's".
It is worth noting that William Blake's patron was Thomas Butts, not William, and that it appears Paula Harper made a mistake with the name, but Dolarhyde knew she was incorrect (I'm assuming this because he didn't verbally agree with her, he just nodded) but didn't want to correct her because he needed to see the Blake painting as quickly as possible.