Hi, I am currently taking real analysis(undergraduate course), and am using the book "Introduction to Real Analysis" by Bartle and Sherbert. I think the book is okay overall, but I was hoping to purchase a secondary text to look at whenever I am confused with a proof or something in the Bartle book. Are any of the Dover books on real analysis any good? They are really cheap and thats what I am looking for. I don't need something to work problems out of, just something else to look at in case I don't understand something in Barte.