Consider the reviews here: http://goo.gl/bGtdsf
Master the grand art of chess calculation by William Friend

try this instead: http://ultimaterank.blogspot.com/
I have bought many chess books and none have had such a positive effect on improving my chess visualisation ability as the above mentioned book. Why it received the negative amazon reviews i truly do not know. I highly recommend this book for improving visualisation accuracy. It is also an excellent games collection book.
I read about this book in few internet pages and called that this a great book on chess calculation.what do you think? Is it great book on calculation?