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...but generally speaking it is good to mention what else is enclosed with the cover letter and thank the person or persons receiving it. Even if it is a standard thank you to "whom it may concern" it is good form to do so. It shows a mark of professionalism.
I've put a few lines about me, a single line about the submission, and my contact information. I'm pretty sure that the cover letter will hardly be looked at until you get selected to write a ten-pager.