APA Citation

 Baker, D. L. (2006).  The unofficial guide to Photoshop Elements 4.  Wiley Pub.

Chicago Style Citation

 Baker, Donna L.  The Unofficial Guide to Photoshop Elements 4.  Wiley Pub, 2006.

MLA Citation

 Baker, Donna L.  The Unofficial Guide to Photoshop Elements 4.  Wiley Pub, 2006.

Warning: These citations may not always be 100% accurate.