Gaya APA
Barell, John. (2007).
Problem-Based Learning (2).
United States of America:
Corwin Press.
Gaya Chicago
Barell, John.
Problem-Based Learning.
2
United States of America:
Corwin Press,
2007.
Teks.
Gaya MLA
Barell, John.
Problem-Based Learning.
2
United States of America:
Corwin Press,
2007.
Teks.
Gaya Turabian
Barell, John.
Problem-Based Learning.
2
United States of America:
Corwin Press,
2007.
Teks.