APA-viite (7. p.)
Princiotta, D., & Fortune, A. (Mar 2009). The Quality Imperative: A State Guide to Achieving the Promise of Extended Learning Opportunities. NGA Center for Best Practices.
Chicago-viite (17. p.)
Princiotta, Daniel, ja Ayeola Fortune. "The Quality Imperative: A State Guide to Achieving the Promise of Extended Learning Opportunities." NGA Center for Best Practices Mar 2009.
MLA-viite (9. p.)
Princiotta, Daniel, ja Ayeola Fortune. "The Quality Imperative: A State Guide to Achieving the Promise of Extended Learning Opportunities." NGA Center for Best Practices, Mar 2009.
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