Trilling, B., & Fadel, C. (2009). 21st century skills: Learning for life in our times. Jossey - Bass Publ.
Čikaški stil citiranja (17. izdanje)Trilling, Bernie, i Charles Fadel. 21st Century Skills: Learning for Life in Our Times. Jossey - Bass Publ, 2009.
MLA način citiranja (8. izdanje)Trilling, Bernie, i Charles Fadel. 21st Century Skills: Learning for Life in Our Times. Jossey - Bass Publ, 2009.
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