Bujang, S.A.A.N. and Mohd Noor, N.N. 2014. Kesan Pembelajaran Berasaskan Masalah (PBM) bagi Topik Ekosistem Terancam Subjek Biologi terhadap Pemikiran Kritis Pelajar: The Effect of Problem-Based Learning (PBL) for Topic of Endangered Ecosystems in Biology Towards Students’ Critical Thinking. Journal of Science and Mathematics Letters. 2, (Dec. 2014), 54–62.