(2007). Secondary School Course Classification System: School Codes for the Exchange of Data. U.S. Department of Education.
Chicago-referens (17:e uppl.)Secondary School Course Classification System: School Codes for the Exchange of Data. U.S. Department of Education, 2007.
MLA-referens (9:e uppl.)Secondary School Course Classification System: School Codes for the Exchange of Data. U.S. Department of Education, 2007.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.