Lamminen, J., M. Leppänen, Risto, A. Kämäräinen, and E. Jokisuu. “A Quantitative Method for Localizing User Interface Problems: The D-TEO Method”. Human Technology, vol. 5, no. 2, Nov. 2009, pp. 121–145, doi:10.17011/ht/urn.200911234467.