|Other Retailer||Price Checked Time||Their Price in AUD||Our Price|
|Amazon US||3 days ago||77.44||$65.60||You save $11.84|
|Amazon UK||yesterday||76.84||$65.60||You save $11.24|
|Book Depository US||today||66.28||$65.60||You save $0.68|
David Heffelfinger is the Chief Technology Officer of Ensode Technology, LLC, a software consulting firm based in the greater Washington DC area. He has been architecting, designing and developing software professionally since 1995 and has been using Java as his primary programming language since 1996. He has worked on many large scale projects for several clients including the US Department of Homeland Security, Freddie Mac, Fannie Mae, and the US Department of Defense. He has a Masters degree in Software Engineering from Southern Methodist University. David is editor in chief of Ensode.net (http://www.ensode.net), a website about Java, Linux, and other technology topics.