C. Alegria and K. Schaeck, On measuring concentration in banking systems, Finance Research Letters, vol.5, issue.1, pp.59-67, 2008.
DOI : 10.1016/j.frl.2007.12.001

J. A. Bikker and K. Haaf, Measures of competition and concentration in the banking industry: a review of the literature, Economic & Financial Modelling, vol.9, issue.2, pp.53-98, 2002.

A. N. Greco, Market Concentration Levels in the U.S. Consumer Book Industry: 19951996, Journal of Cultural Economics, vol.24, issue.4, pp.321-336, 2000.
DOI : 10.1023/A:1007654222498

C. Gwin, A guide for industry study and the analysis of firms and competitive strategy

T. H. Hannan, Market share inequality, the number of competitors, and the HHI: An examination of bank pricing, Review of Industrial Organization, vol.12, issue.1, pp.23-35, 1997.
DOI : 10.1023/A:1007744119377

A. O. Hirschman, The paternity of an index, American Economic Review, vol.54, issue.5, p.761, 1964.

A. Hirschman, National Power and the Structure of Foreign Trade. California Library reprint series, 1945.

H. Van-kranenburg, Mobility and Market Structure in the Dutch Daily Newspaper Market Segments, Journal of Media Economics, vol.15, issue.2, pp.107-123, 2002.
DOI : 10.1207/S15327736ME1502_3

M. G. Lijesen, P. Nijkamp, and P. Rietveld, Measuring competition in civil aviation, Journal of Air Transport Management, vol.8, issue.3, pp.189-197, 2002.
DOI : 10.1016/S0969-6997(01)00048-5

C. Liston-heyes and A. Pilkington, Inventive concentration in the production of green technology: a comparative analysis of fuel cell patents, Science and Public Policy, vol.31, issue.1, pp.15-25, 2004.
DOI : 10.3152/147154304781780190

R. Lopez, A. Azzam, and C. Lirn-espaa, Market Power and/or Efficiency: A Structural Approach, Review of Industrial Organization, vol.20, issue.2, pp.115-126, 2002.
DOI : 10.1023/A:1013867114881

M. Naldi, Concentration indices and Zipf???s law, Economics Letters, vol.78, issue.3, pp.329-334, 2003.
DOI : 10.1016/S0165-1765(02)00251-3

M. Naldi and M. Flamini, Interval Estimation of the Herfindahl-Hirschman Index under Incomplete Market Information, 2014 UKSim-AMSS 16th International Conference on Computer Modelling and Simulation, pp.317-322, 2014.
DOI : 10.1109/UKSim.2014.66

M. Naldi and C. Salaris, Rank-size distribution of teletraffic and customers over a wide area network, European Transactions on Telecommunications, vol.16, issue.4, pp.415-421, 2006.
DOI : 10.1002/ett.1084

E. M. Noam, Did AT&T Die in Vain? An Empirical Comparison of AT&T and Bell Canada, Federal Communications Law Journal, vol.61, issue.1, 2008.

E. M. Noam, Who Owns the Worlds Media? Research Paper 13- 22, Columbia Business School, 2013.

S. A. Rhoades, The Herfindahl-Hirschman index, Federal Reserve Bulletin, pp.188-189, 1993.

U. S. The, Department of Justice and the Federal Trade Commission: Horizontal Merger Guidelines, 2010.

U. S. Bureau, Concentration ratios, available at http://www.census.gov/ econ/concentration.html 22. VV.AA.: Quarterly telecommunication markets observatory, Autorità per le Garanzie nelle Telecomunicazioni, pp.51-506, 2013.

D. S. Weinstock, Using the Herfindahl Index to measure concentration. The Antitrust Bulletin pp, pp.285-301, 1982.

K. Ye, W. Lu, and W. Jiang, Concentration in the international construction market, Construction Management and Economics, vol.56, issue.12, pp.1197-1207, 2009.
DOI : 10.1111/j.1744-1714.1976.tb00457.x