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2. B. DePorter and M. Hernacki, Quantum Learning: Membiasakan Belajar Nyaman dan Menyenangkan (PT Mizan Pustaka, Bandung, 2011) p. 16.
3. B. DePorter, M. Reardon, and S. S. Nourie, Quantum Teaching: Mempraktikan Quantum Learning di Ruang-Ruang Kelas (PT Mizan Pustaka, Bandung, 2010) p. 39–40.
4. D. Muijs and D. Reynolds, Effective teaching: evidence and practice 2nd ed, (SAGE Publications Ltd, London, 2005), p. 212.
5. Educational Technology Division Ministry of Education, Project-Based Learning Handbook: Educating the Millennial Learner (Ministry of Education Malaysia, Kuala Lumpur, 2006) p. 22.