In my field, there often is absolutely no difference at all between one edition and the next other than the pagination. Drives me crazy cause all my marginal comments become useless. And college bookstores!!!! We outsourced ours to a Barnes and Noble franchise and the price has gone through the roof while service has sunk below the 9th circle of hell. The markup for some of the books I use was up to 40% and more. And for course packs--last time I had one made the price was 100 bucks. Since then I've found on-line alternatives, so suck it, bookstore.
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