N. C. M. Q. F. Ferreira, F. A. F. Ferreira, C. S. E. Marques, G. O. Pérez-Bustamante Ilander, and A. Çipi, “Challenges in the implementation of public electronic services: lessons from a regional-based study”, JBEM, vol. 16, no. 5, pp. 962–979, Oct. 2015, doi: 10.3846/16111699.2014.920718.