(2000). Percentage of the Population who Completed Secondary & Higher Education. U.S. Department of Education.
芝加哥风格引文Percentage of the Population Who Completed Secondary & Higher Education. U.S. Department of Education, 2000.
MLA引文Percentage of the Population Who Completed Secondary & Higher Education. U.S. Department of Education, 2000.
警告：这些引文格式不一定是100％准确.