M. Y. . Idris, Z. . Tahir, S. . Ishak, F. U. M. . Azian, and N. . Lyndon, “Assessing the impact of ecosystem factors on oil palm smallholder productivity: Evidence from Bakong and Marudi, Sarawak”, ijirss, vol. 8, no. 8, pp. 351–360, Oct. 2025.