Google: " filetype:pdf inurl:studiolab.ide.tudelft.nl"
Some papers by professors Desmet, Stappers, and Hekkert are good.
Relating to that are articles from the DQI group at Eindhoven University of Technology - very innovation- and product design related, and always remaining practically oriented - http://dqi.id.tue.nl/web/
Also check out UXMag http://uxmag.com/
There is definitely a need for an international professional magazine for ID’ers, it shows how young a profession this is.