Bateman, S., Gutwin, C., & Nacenta, M. (2008). Seeing things in the clouds: the effect of visual features on tag cloud selections.
In Proceedings of the nineteenth ACM conference on Hypertext and hypermedia, HT '08 (pp. 193-202). New York, NY, USA:

Chekit (2010). Chekit Nationale Search Engine Monitor.

Garner, R. (2009). Google Ups Share of Search To 72%; Yahoo, MSN and Ask Continue To Tank.

Kao, G. Y.-M., Lei, P.-L., & Sun, C.-T. (2008). Thinking style impacts on Web search strategies.
Computers in Human Behavior, 24(4), 1330-1341.Elsevier

Kuo, B. Y.-L., Hentrich, T., Good, B. M., & Wilkinson, M. D. (2007). Tag clouds for summarizing web search results.
In Proceedings of the 16th international conference on World Wide Web, WWW '07 (pp. 1203-1204). New York, NY, USA: ACM.

Lohmann, S., Ziegler, J., & Tetzlaff, L. (2009). Comparison of Tag Cloud Layouts: Task-Related Performance and Visual Exploration, volume 5726 of Lecture Notes in Computer Science, (pp. 392-404).
Springer Berlin / Heidelberg.Springer

Mirizzi, R., Ragone, A., Noia, T. D., & Sciascio, E. D. (2010). What if Exploratory Search and Web Search meet?⋆.
Proceedings of the Fourth Ph.D.Workshop in

Rivadeneira, A. W., Gruen, D. M., Muller, M. J., & Millen, D. R. (2007). Getting our head in the clouds: toward evaluation studies of tagclouds.
In Proceedings of the SIGCHI conference on Human factors in computing systems, CHI '07 (pp. 995-998). New York, NY, USA:

Sinclair, J. & Cardew-Hall, M. (2008). The folksonomy tag cloud: when is it useful?
Journal of Information Science, 34(1), 15-29.

Spink, A., Wolfram, D., Jansen, M. B. J., & Saracevic, T. (2001). Searching the web: The public and their queries.
Journal of the American Society for Information Science and Technology, 52(3), 226-234.Wiley Online

van Zwol, R. & van Oostendorp, H. (2004). Google’s “I’m Feeling Lucky”, Truly a Gamble?, volume 3306 of Lecture Notes in Computer Science, (pp. 378-389).
Springer Berlin / Heidelberg.Springer