There are at least three types of books on testing:
1) For test engineers/test managers: about testing whole product/system
2) Books for developers - about unit tests, bugs, etc.
3) Specific books on very specific topics.
My recommendations for first two categories are:
"Systematic Software Testing" by Rick D. Craig, Stefan P. Jaskiel
"Testing computer software" by Cem Kaner, Jack Falk, Hung Q. Nguyen
And a new one:
"Effective Software Testing: 50 Specific Ways to Improve Your Testing" by Elfriede Dustin
?:the art of a constructive conflict perceived as a destructive diagnose.