ebrary, Inc. (2010). The future of the natural gas market in South East Europe. World Bank.
芝加哥风格引文ebrary, Inc. The Future of the Natural Gas Market in South East Europe. Washington, D.C.: World Bank, 2010.
MLA引文ebrary, Inc. The Future of the Natural Gas Market in South East Europe. World Bank, 2010.
警告：这些引文格式不一定是100％准确.