(2000). Average Math & Science Performance Scores of 4th- Grade Students. U.S. Department of Education.
Chicago-viite (17. p.)Average Math & Science Performance Scores of 4th- Grade Students. U.S. Department of Education, 2000.
MLA-viite (9. p.)Average Math & Science Performance Scores of 4th- Grade Students. U.S. Department of Education, 2000.
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