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 Aug. 12];6(1):26-3. Available from: https://journal.uthm.edu.my/index.php/jsmbe/article/view/20562