Delgoshaei, A., Ariffin, M. K., Bin Baharudin, B. T. H. T., & Leman, Z. (2014). A Backward Approach for Maximizing Net Present Value of Multi-mode Pre-emptive Resource-Constrained Project Scheduling Problem with Discounted Cash Flows Using Simulated Annealing Algorithm. International Journal of Industrial Engineering and Management, 5(3), 151–158. https://doi.org/10.24867/IJIEM-2014-3-117