Robert Morrow 
Bluetooth: Operation and Use [PDF ebook] 

Unlike most other references on the market, this next-generation resource goes well beyond Bluetooth specifications and thoroughly examines different implementation approaches–as taught by a "master instructor."* Discusses Bluetooth in detail, covering both operational characteristics as well as its use in a wireless communications system* Addresses the coexistence of Bluetooth’s with other wireless networks* Provides information on the significant security problems that exist when communicating without wires* Based on 2 very popular and highly effective courses the author has been teaching for more than a year