A. Harrer, S. Ziebarth, A. Giemza, и H. Hoppe. The 8th IEEE International Conference on Advanced Learning Technologies, стр. 41-45. Santander, Spain, IEEE Computer Society Press, (2008)
V. Dodge, и S. Vine. Communities of Practice: Creating Learning Environments for Educators, 2, глава 19, Information Age Publishing, Charlotte, NC, (2008)