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So, this book is so compact that many tests are actually not there. It has too many irrelevant or empty tests so that it put the number 64 on the cover. I just did a few tests and then skimmed through many others. Totally not worth it.
Exactly what the name suggests. It's a curation of all the different kinds of (largely behavioural science based) tests. It has some tests and their interpretations given outright and for others, there's at least enough information for the reader to understand what to expect from the test.