Why don't you just focus on The Cask of Amontillado and how it's connected to the Gothic period. What was the Gothic movement? How is this story Gothic. What in Poe's story makes him Gothic. If you want to add a poem, use one of Poe's poems. I don't think you would have any trouble finding scholarly source material for either Poe or Poe and the Gothic period. Go to JStor. If you need help, let me know