(2007). Secondary School Course Classification System: School Codes for the Exchange of Data. U.S. Department of Education.
Chicago-viite (17. p.)Secondary School Course Classification System: School Codes for the Exchange of Data. U.S. Department of Education, 2007.
MLA-viite (9. p.)Secondary School Course Classification System: School Codes for the Exchange of Data. U.S. Department of Education, 2007.
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