Joop, J. B. (2015). (Vol. 37) [PhD thesis]. Eul Verlag.
PhD thesis by Björn Joop
Betz, M., Glukhova, A., Joop, B., & Veiel, D. (2008). In P. Isaías, B. M. Nunes, & D. Ifenthaler (Eds.), Proceedings of the IADIS International Conference WWW INTERNET 2008 Freiburg, Germany. IADIS Press.