APA   Click to copy
Karapanos, E. E., Zimmerman, J., Forlizzi, J., & Martens, J. J.-B. (2009). User experience over time: an initial framework. Human Factors in Computing Systems, 729–738.

Chicago/Turabian   Click to copy
Karapanos, E Evangelos, J Zimmerman, J Forlizzi, and Jbos Jean-Bernard Martens. “User Experience over Time: an Initial Framework.” Human Factors in Computing Systems (March 3, 2009): 729–738.

MLA   Click to copy
Karapanos, E. Evangelos, et al. “User Experience over Time: an Initial Framework.” Human Factors in Computing Systems, Mar. 2009, pp. 729–38.

@article{e2009a,
  title = {User experience over time: an initial framework},
  year = {2009},
  month = mar,
  day = {3},
  journal = {Human Factors in Computing Systems},
  pages = {729-738},
  author = {Karapanos, E Evangelos and Zimmerman, J and Forlizzi, J and Martens, Jbos Jean-Bernard},
  booktitle = {chi},
  month_numeric = {3}
}