Why web 2.0 is good for learning and for research: principles and prototypes. - Carsten Ullrich; Kerstin Borau; Heng Luo; Xiaohong Tan; Liping Shen; Ruimin Shen (WWW, 2008)

Microblogging for Language Learning: Using Twitter to Train Communicative and Cultural Competence. - Kerstin Borau; Carsten Ullrich; Jinjin Feng; Ruimin Shen (ICWL, 2009)

Who Students Interact With? A Social Network Analysis Perspective on the Use of Twitter in Language Learning. - Carsten Ullrich; Kerstin Borau; Karen Stepanyan (EC-TEL, 2010)

A Social Network Analysis Perspective on Student Interaction within the Twitter Microblogging Environment. - Karen Stepanyan; Kerstin Borau; Carsten Ullrich (ICALT, 2010)

Cross-Cultural Multimedia Language Learning: Case Study and Analysis. - Carsten Ullrich; Kerstin Borau; Scott Grant; Daniel Jackson 004; Ruimin Shen (ICWL, 2010)

Learning from Learning Objects and Their Repositories to Create Sustainable Educational App Environments. - Carsten Ullrich; Ruimin Shen; Kerstin Borau (ICALT, 2013)