Grahl, M., Hotho, A. & Stumme, G. (2007). Conceptual Clustering of Social Bookmark Sites. In A. Hinneburg (ed.), Workshop Proceedings of Lernen -- Wissensentdeckung -- Adaptivität (LWA 2007) (p./pp. 50-54), September, : Martin-Luther-Universität Halle-Wittenberg. ISBN: 978-3-86010-907-6

Grahl, M., Hotho, A. & Stumme, G. (2007). Conceptual Clustering of Social Bookmark Sites. In A. Hinneburg (ed.), Workshop Proceedings of Lernen -- Wissensentdeckung -- Adaptivität (LWA 2007) (p./pp. 50-54), September, : Martin-Luther-Universität Halle-Wittenberg. ISBN: 978-3-86010-907-6

Grahl, M., Hotho, A. & Stumme, G. (2007). Conceptual Clustering of Social Bookmarking Sites. 7th International Conference on Knowledge Management (I-KNOW '07) (p./pp. 356-364), SEP, Graz, Austria: Know-Center.