A. Internet-inc, The Top 500 Sites on the Web

. Facebook, Updating Our Terms and Policies: Helping You Understand How Facebook Works and How to Control Your Information

D. Melanson, Facebook Reports $1.81 Billion in Revenue for Q2 2013, 1.15 Billion Monthly Active Users

. Statista, Facebook's global revenue as of 1st quarter 2015, by segment (in million U.S. dollars), http://www.statista.com/statistics/277963/facebooks-quarterly-global-revenue-by- segment

J. Moorthy, R. Lahiri, N. Biswas, D. Sanyal, J. Ranjan et al., Big Data: Prospects and Challenges, Vikalpa, vol.40, issue.1, pp.74-96, 2015.
DOI : 10.1177/0256090915575450

E. K. Clemons, Business Models for Monetizing Internet Applications and Web Sites: Experience, Theory, and Predictions, Journal of Management Information Systems, vol.26, issue.2, pp.15-41, 2009.
DOI : 10.2753/MIS0742-1222260202

D. Zambonini, Monetizing Your Web App: Business Model Options

Z. Vukanovic, New Media Business Models in Social and Web Media, Journal of Media Business Studies, vol.8, issue.3, pp.51-67, 2011.
DOI : 10.1080/16522354.2011.11073526

P. B. Goes, Big Data and IS Research, MIS Quarterly, vol.38, p.iii?viii, 2014.

A. M. Kaplan and M. Haenlein, Users of the world, unite! The challenges and opportunities of Social Media, Business Horizons, vol.53, issue.1, pp.59-68, 2010.
DOI : 10.1016/j.bushor.2009.09.003

I. Chiang, C. Huang, and C. Huang, Characterizing Web users' degree of Web 2.0-ness, Journal of the American Society for Information Science and Technology, vol.3, issue.2, pp.1349-1357, 2009.
DOI : 10.1002/asi.21058

D. Boyd and N. B. Ellison, Social Network Sites: Definition, History, and Scholarship, Journal of Computer-Mediated Communication, vol.3, issue.1, pp.210-230, 2007.
DOI : 10.1111/j.1083-6101.2007.00393.x

C. Maier, S. Laumer, and T. Weitzel, Although I am stressed, I still use IT! Theorizing the decisive impact of strain and addiction of social network site users in post-acceptance theory, Proceedings of 34th International Conference on Information Systems, 2013.

A. Wilhelm, Facebook's Desktop Ad Revenues Fell $26m in Q3 as Its Mobile Ad Revenue Surged $226mfacebooks-desktop-ad-revenues- fell-26m-in-q3-as-its-mobile-ad-revenue-surged-226m, 2013.

K. Gatto and K. Crawford, How Facebook Sells Your Personal Information, http://news.discovery.com/tech/gear-and-gadgets/how-facebook-sells-your-personal- information-1301241, Critical questions for big data. Information, Communication & Society, pp.662-679, 2012.

K. Johnston, What Are the Advantages of Mobile Advertising?

R. K. Yin, Case study research. Design and methods, 1994.

L. Dubé and G. Paré, Rigor in Information Systems Positivist Case Research: Current Practices, Trends, and Recommendations, MIS Quarterly, vol.27, pp.597-635, 2003.
DOI : 10.4135/9781473915480.n65

I. Benbasat, D. K. Goldstein, and M. Mead, The Case Research Strategy in Studies of Information Systems, MIS Quarterly, vol.11, issue.3, pp.369-386, 1987.
DOI : 10.2307/248684

K. M. Eisenhardt, Building Theories from Case Study Research, Academy of Management Review, vol.14, pp.532-550, 1989.

N. Mays and C. Pope, Qualitative Research: Rigour and qualitative research, BMJ, vol.311, issue.6997, pp.109-112, 1995.
DOI : 10.1136/bmj.311.6997.109

M. B. Miles and A. M. Huberman, Qualitative data analysis. An expanded sourcebook, 1994.

A. S. Lee, A Scientific Methodology for MIS Case Studies, MIS Quarterly, vol.13, issue.1, pp.33-50, 1989.
DOI : 10.2307/248698

S. Sawyer, Analysis by Long Walk, Idea Group Pub, 2001.
DOI : 10.4018/978-1-930708-06-8.ch007

R. Nisbett and L. Ross, Human inference. Strategies and shortcomings of social judgment, 1980.

J. F. Hair, Multivariate data analysis, 2010.

P. R. Stopher, Collecting, managing, and assessing data using sample surveys, 2012.
DOI : 10.1017/CBO9780511977893

J. Strategy and &. Research, Virtual Currency and Social Network Payments ? the New Gold Rush: How Emerging Virtual Transactions Will Alter the Payments Landscape Forever, p.212, 2011.

C. Ho and T. Wu, Factors Affecting Intent to Purchase Virtual Goods in Online Games, International Journal of Electronic Business Management, vol.10, pp.204-212, 2012.

A. Animesh, P. Alain, Y. Sung-byung, and O. Wonseok, An odyssey into virtual worlds: exploring the impacts of technological and spatial environments on intention to purchase virtual products, MIS Quarterly, vol.35, pp.789-810, 2011.

Y. Guo and S. Barnes, Virtual item purchase behavior in virtual worlds: an??exploratory investigation, Electronic Commerce Research, vol.27, issue.3, pp.77-96, 2009.
DOI : 10.1007/s10660-009-9032-6

C. Anderson, Free: the past and future of a radical price, 2009.

M. F. Niculescu and D. J. Wu, When Should Software Firms Commercialize New Products Via Freemium Business Models?, SSRN Electronic Journal, 2011.
DOI : 10.2139/ssrn.1853603
URL : http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.220.9580

E. Eldon, Facebook Sets Deadline to Make Credits Sole Canvas Game Payment Option, http://www.adweek.com/socialtimes/facebook-sets-july-1-2011-deadline-to- make-credits-sole-canvas-game-payment-option, 2011.

A. Osterwalder and Y. Pigneur, Business Model Generation: A Handbook for Visionaries, Game Changers, and Challengers, 2013.