Hale, J. A. (2012). Performance-based certification: How to design a valid, defensible, cost-effective program (2nd ed.). Pfeiffer.
Chicago-viite (17. p.)Hale, Judith A. Performance-based Certification: How to Design a Valid, Defensible, Cost-effective Program. 2nd ed. San Francisco: Pfeiffer, 2012.
MLA-viite (9. p.)Hale, Judith A. Performance-based Certification: How to Design a Valid, Defensible, Cost-effective Program. 2nd ed. Pfeiffer, 2012.
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