APA-referens (7:e uppl.)
Torp, L., & Sage, S. (2002). Problems as possibilities: Problem-based learning for K-16 education. Association for Supervision & Curriculum Development.
Chicago-referens (17:e uppl.)
Torp, Linda, och Sara Sage. Problems as Possibilities: Problem-based Learning for K-16 Education. Alexandria, Va.: Association for Supervision & Curriculum Development, 2002.
MLA-referens (9:e uppl.)
Torp, Linda, och Sara Sage. Problems as Possibilities: Problem-based Learning for K-16 Education. Association for Supervision & Curriculum Development, 2002.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.