Cita APA (7th ed.)

Noumba Um, P. (2004). A model for calculating interconnection costs in telecommunications. World Bank : PPIAF.

Cita Chicago (17th ed.)

Noumba Um, Paul. A Model for Calculating Interconnection Costs in Telecommunications. Washington, D.C.: World Bank : PPIAF, 2004.

Cita MLA (9th ed.)

Noumba Um, Paul. A Model for Calculating Interconnection Costs in Telecommunications. World Bank : PPIAF, 2004.