Jacky Tai has authored 7 highly-acclaimed brand strategy books that are very easy to read and very practical because he is a practitioner, not an academic and he knows that anyone involved in running a business or managing a brand these days have no time for theoretical fluff.  His books contain many real case studies of clients he has served and also very useful branding techniques that are used by him in his daily work.  These books are available on Amazon.com.