(2005). enviromental standards and competitiveness of key economic sectors. united nations.
芝加哥风格引文Enviromental Standards and Competitiveness of Key Economic Sectors. new york: united nations, 2005.
MLA引文Enviromental Standards and Competitiveness of Key Economic Sectors. united nations, 2005.
警告：这些引文格式不一定是100％准确.