Laffont, J., Estache, A., & Zhang, X. (2004). Universal service obligations in developing countries. World Bank.
Chicago Style aipamenaLaffont, Jean-Jacques, Antonio Estache, and Xinzhu Zhang. Universal Service Obligations in Developing Countries. Washington, D.C: World Bank, 2004.
MLA aipamenaLaffont, Jean-Jacques, et al. Universal Service Obligations in Developing Countries. World Bank, 2004.
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