Did you ever wonder who designs book covers? I never gave it much thought until I heard this interesting interview.
Technically cover artwork is copyrighted material however copyright law has four Fair Use provisions. Stanford Libraries notes that "fair use is any copying of copyrighted material done for a limited and “transformative” purpose, such as to comment upon, criticize, or parody a copyrighted work." In this case I would argue that you are commenting or reviewing the copyrighted work.
For this project you may use a picture of the cover or take your own. You do not need to cite the book cover.