The Word Biblical Commentary, Volume 40 | WBC 2 Corinthians by Ralph P. Martin has a 1st ed. and a 2nd ed.
The one that's listed in the Commentary Sale at $20.99 is the 1st ed. If you click on the blue "Add to cart", that's the one that will get added to your cart. If you click on the book cover image, you'll be taken to the 2nd edition page, priced at $54.99. This is actually a good thing, but a little confusing, as it lets you know there are 2 editions and allows you to make a choice. The 2nd ed. is not on sale.
