My sister, who is a teacher, just discovered that a statement of opinion from a one Dr Henry Valdez, a professor at Miskatonic University, is present in the teaching materials that third-party content writers provided to her and all her other co-workers. It's presented as a real place, with real students.
She discovered it after a student of hers cited the source in an assignment. None of her co-teachers or her principal knew it was there, or even what it is.