Lee, Sun-Sook and Yong, Hwan-Seung. "TagPlus: A Retrieval System using Synonym Tag in Folksonomy." Paper presented at the meeting of the Proceedings of the 2007 International Conference on Multimedia and Ubiquitous Engineering, Washington, DC, USA, 2007.
Nunninger, Thomas. "Calculating Relevancy when Searching in Semantically and Hierarchically Structured Data as Exemplified with the eZ Publish Enterprise Content Management System�s Internal Search Engine." Masters thesis, Albert-Ludwigs-Universit�t Freiburg, 2007.