Robertson, J. G., & Fitzgerald, B. (2013). Drupal for education and e-learning: Create web-based, content-rich tools for teaching and learning (2nd ed.). Packt Pub..

Robertson, James G., and Bill Fitzgerald. Drupal for Education and E-learning: Create Web-based, Content-rich Tools for Teaching and Learning. 2nd ed. Birmingham: Packt Pub., 2013.

Robertson, James G., and Bill Fitzgerald. Drupal for Education and E-learning: Create Web-based, Content-rich Tools for Teaching and Learning. 2nd ed. Packt Pub., 2013.