World Health Organization. (2000). Air quality guidelines for europe (2nd-ed.). World Health Organization.
芝加哥风格引文World Health Organization. Air Quality Guidelines for Europe. 2nd-ed. Copenhagen: World Health Organization, 2000.
MLA引文World Health Organization. Air Quality Guidelines for Europe. 2nd-ed. World Health Organization, 2000.
警告：这些引文格式不一定是100％准确.