Prayogo, Doddy, and Christianto Tirta Kusuma. “Optimization of Resource Leveling Problem under Multiple Objective Criteria Using a Symbiotic Organisms Search”. Civil Engineering Dimension 21, no. 1 (March 1, 2019): 43–51. Accessed October 4, 2025. https://ced.petra.ac.id/index.php/civ/article/view/21502.