Muhammad Hafizuddin Isa, Siti Khalijah Yaman. Productivity Assessment in Roofing and Wall Painting Works Using Direct Observation Methods at Construction Site. JSMBE [Internet]. 2026 Jun. 30 [cited 2026 Jul. 24];6(1):26-3. Available from: https://publisher.uthm.edu.my/ojs/index.php/jsmbe/article/view/20562