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Title: So sad
Review: Sadly, not useful. No formulas, but trivial ones, can be read. The preview is of a different (useful) version, though there isn't a proper warning; it does mention that it is a different book you view, but for a math/physics book it would only be fair to inform that formulas were demolished by the OCR handling. The claim in the book that most of their books are freely available as digital copies does not fare much better. You have to pay $9.99 for the "free digital copy". Luckily, Google Books have the book.
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