Küpper, A. and Treu, G. (2010). Next Generation Location-based Services: Merging Positioning and Web 2.0. Mobile Intelligence: When Computational Intelligence Meets Mobile Paradigm. John Wiley & Sons, 213-238.

Kessel, M. and Ruppel, P. and Gschwandtner, F. (2010). BIGML: A Location Model with Individual Waypoint Graphs for Indoor Location-based Services. PIK - Praxis in der Informationsverarbeitung und Kommunikation. De Gruyter Saur Verlag, 260-266.

Ruppel, P. and Gschwandtner, F. and Schindhelm, C. K. and Linnhoff-Popien, C. (2009). Indoor Navigation on Distributed Stationary Display Systems. Proceedings of the 33rd Annual IEEE Intl. Computer Software and Applications Conference (COMPSAC 2009)

Ruppel, P. and Gschwandtner, F. (2009). Spontaneous and Privacy-friendly Mobile Indoor Routing and Navigation. Proceedings of the 2nd Workshop on Services, Platforms, Innovations and Research for new Infrastructures in Telecommunications (SPIRIT 2009)

Gschwandtner, F. and Ruppel, P. (2008). Automatic Calibration of Large-scale WiFi-Positioning Systems. IEEE Global Communications Conference - Design & Developers Forum

Ruppel, P. and Klein, C. and Linnhoff-Popien, C. (2008). Indooria – A Platform for Proactive Indoor Location-based Services. IEEE Global Communications Conference - Design & Developers Forum

Deblauwe, N. and Ruppel, P. and van Biesen, L. (2008). Modelling the GPS-receiver: a look from the LBS-side. Proceedings of the European Navigation Conference (ENC-GNSS)

Kjärgaard, M. B. and Treu, G. and Ruppel, P. and Küpper, A. (2008). Efficient Indoor Proximity and Separation Detection for Location Fingerprinting. Proceedings of the 1st Intl. Conference on MOBILe Wireless MiddleWARE, Operating Systems, and Applications (Mobilware 2008)

Prinz, V. and Fuchs, F. and Ruppel, P. and Gerdes, C. and Southall, A. (2008). Adaptive and Fault-Tolerant Service Composition in Peer-to-Peer Systems. Proceedings of the 8th IFIP Intl. Conference on Distributed Applications and Interoperable Systems (DAIS 2008). Springer, 30-43.

Treu, G. and Fuchs, F. and Martens, J. and Ruppel, P. and Weiß, D. and Küpper, A. and Linnhoff-Popien, C. (2007). Sozialverträgliche Autorisierung des Zugriffs auf Ortsinformationen. Tagungsband des 4. GI/ITG KuVS Fachgesprächs zu Ortsbezogene Anwendungen und Diensten. Verlag Dr. Hut, 82-86.

Deblauwe, N. and Ruppel, P. (2007). Combining GPS and GSM Cell-ID positioning for Proactive Location-based Services. Proceedings of the 4th Annual Intl. Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services (MOBIQUITOUS), 1-7.

Ruppel, P. and Treu, G. and Küpper, A. and Linnhoff-Popien, C. (2006). Anonymous User Tracking for Location-based Community Services. Proceedings of the 2nd Intl. Workshop on Location and Context-Awareness. Springer, 116-133.

Martens, J. and Treu, G. and Ruppel, P. and Weiss, D. and Küpper, A. and Linnhoff-Popien, C. (2006). Eine Plattform zur Unterstützung von proaktiven ortsbezogenen Mehrbenutzer-Anwendungen. Tagungsband zum 3. GI/ITG KuVS Fachgespräch zu Ortsbezogene Anwendungen und Diensten

Treu, G. and Küpper, A. and Ruppel, P. (2005). Anonymization in Proactive Location Based Community Services. Advances in Pervasive Computing. Adjunct Proceedings of the Third Intl. Conference on Pervasive Computing. Österreichische Computer Gesellschaft.