World Bank Group. (1999). Natural gas: Private sector participation and market development. World Bank Group.
Chicago-referens (17:e uppl.)World Bank Group. Natural Gas: Private Sector Participation and Market Development. Washington, D.C: World Bank Group, 1999.
MLA-referens (9:e uppl.)World Bank Group. Natural Gas: Private Sector Participation and Market Development. World Bank Group, 1999.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.